Full disclosure: I received this book for free as part of a Goodreads giveaway, but I'll do my best to give it a fair and honest review.
Zero Echo Shadow Prime tells the story of Charlie Nobunga, a young genius who just programmed a new sort of AI assistant that actually feels like a real person. In the midst of her fame, she's diagnosed with cancer, the same kind that killed her twin sister, but the head of a cutting edge technology company proposes a solution... to scan her brain and copy her personality into a stronger, artificial body. Charlie's unsure about the whole thing, but the procedure goes ahead... and many different Charlies awaken, each unaware of the others, sometimes unaware of a lot more. First, there's Prime, the planned superior body, a form that could be a cyborg supersolider. There's also Echo, a four-armed warrior with no memories, in a digital world full of other, slightly different Echos. There's Shadow, who's been converted into an AI assistant in somebody's head. And finally, there's Charlie's original body, which wasn't destroyed during the scan but never intended to be reawoken unless there was a problem... except it's been kidnapped by Luddites, who want her help to take down the company that scanned her.
This book's not only a first novel, but a self-published one. This normally makes me very leery of potential poor quality works (I've been burned before), although I'm certainly willing to give a first novel a little more leeway, and the book's concept was impressive and ambitious. So does it live up to it, and is it a successful novel that you could expect to get published on its own?
The answer to both questions is, yes, mostly. Some flaws (and I will get a little nitpicky about them, but only in the hopes of helping the author improve), but clearly this is an author with a lot of potential. The story is well-paced and the changes in perspective keep you interested, and what could turn out to be a complicated mess, with many copies of the same people running around, never falls outside his control. The stories are separate at first, but tie together in believable ways and with excellent timing, neither too slowly or too quick (although maybe I'd have liked a little more solo time on a couple of them). For the most part the science and technology is believable without being overwhelming. In fact, I think this is quite a good novel to introduce people to various singularity-type themes without requiring them to be versed in a lot of prior SF.
As for the flaws? Well, a lot of it depends on whether this is intended to be a full-on SF novel, or a (higher-age) Young Adult SF book. It's not absolutely clear from the descriptions and promotion, but there are a few markers for option B. The character being 18, for example, suggests it may be marketed towards teens, and the romance angle felt a little on the YA side, opposite sides, immediate attraction and suddenly falling for each others. However a few things point in the other direction, like the ending which seems to set up for a sequel that is decidedly less YA and more complex.
The prose is pretty good, overall, but I did notice some examples of what's called "Said Bookism", where the author notably avoids using the word "said", and instead characters insist, implore, chime in, drone, and so on, some of which is certainly okay for variety, but when it's done too often, it can be distracting. In this case, it's on the edge of being a problem, so this is one of the nitpicky points, something the author should be careful of in the future. Some parts are worse than others, but it's not a huge problem overall.
Charlie's big development that led to her Shadow winning the Turing test seems a little facile, described as a stunning breakthrough, when really it seems like a fairly obvious thing that would be tried many times in many different ways. Similarly, the "replicator" she invents is a little sci-cute rather than consistant and thought out (if it's possible under the technology of the world, there ought to be a lot of them produced by a lot of people, a big problem that society has ways to deal with). Both of these are things I'd completely overlook if I were to consider it a YA novel... the main characters being sort of exceptional-in-a-way-that's-easy-for-the-audience-to-relate-to is a common trope, and it's easier to give her a simple insight that for some reason nobody else has thought of than bog the younger reader down with a lot of technical gobbledegook. But I'd like a little more rigor in a full-fledged, no-qualifier SF novel.
Another thing in that category (things that are more forgiveable if you consider the book to be a YA) is one of my minor disappointments in the book. There seems like a lot of characters, but... in many ways, there's really one character, seen in many different ways and contexts, sometimes interacting with herself. But, in the end, I wound up finding her a little bland as a character: a generally good person who's smart and has a real stubborn streak. The almost archetypical hero, with only a few details above and beyond that. In a YA, this isn't a problem (and may even be ideal) because a somewhat bland character is easier to project yourself into and inhabit, and it can become less about who the character is as it is about what you might do in that situation. But in a more adult, deeper work, I'd expect a lot more exploration into what certain characteristics lead to which parts of our personality, how removing memory or putting us in complex scenarios might alter our natures, how an invulnerable Charlie is different from one dying of cancer, at the very least, know that feature character inside out. But after reading about all these different versions, I never really got the sense that I knew the character any better, any more deeply, than I would in a TV show. There's a bit of a difference between the Echos and the others, but most of that is caused by stuff that happens off page and left for a potential sequel.
There is one final bit that rankled me particularly, and that's involving Charlie's cancer. First, the idea that cancer is still a worry in a world where nanotechnology can build new bodies for people from scratch is one of those few inconsistent moments (surely it would be easier to have some nano searching her body for tumors and eliminating them... even if it couldn't be a full cure, something to make her functional instead of sickly), but that's not even my biggest problem. My biggest problem is there's a point in the story where Charlie is told "Cancer's an electrolyte imbalance, chemo is the worst thing you can do," and told to drink something. Now, this is a Luddite character who may not know what they're talking about, but... it's never really refuted in the story, either, and she's portrayed as educated in this field particularly. A lot of their other ideas are shown to be wrong, but at other points it's clear they might have some valid points, and in the case of this cancer cure... it's an awfully specific claim about cancer that borders on woo and could wind up hurting real people if they took it on faith as they might many of the other technological advancements. That bothered me. I wouldn't even mind if they still claimed they have a cure for cancer (true or not), as long as they weren't specific about how it worked and claim that current medical advice is the WORST thing you could do... but if you're going to declare something about a real medical condition that goes directly against current medical thinking, I think it's your responsibility to either prove it, declare it explicitly an alternate universe that has no basis in fact, or refute it directly in the text.
Otherwise, it's a very solid first novel. So yes, there are flaws, but even a professional first novel from one of the big publishing companies might have issues like these, and they don't seriously harm the book. On the whole, I was engaged, never bored, and always looking forward to what happened next. The ultimate test of a first novel is, would I read a sequel (or another novel by the author), and the answer in this case is an unequivocal yes (particularly a sequel). A final rating is still somewhat complicated, because as a normal SF book, it's good and shows a lot of potential, but takes a few too many shortcuts and so it's not quite up there with my favorites. I'd put it as a high three, maybe getting close to four. If I were to consider this a Young Adult book (again, edging towards the higher end of the teen years), it comes off much better. In fact, I'd wager to say it's probably one of the most enjoyable YA pure-SF books I've read (although admittedly, there aren't many). I'd put it firmly in four territory, and if Goodreads allowed half-stars, a 4.5 might be what I'd score it. I guess the best thing to do is split the difference and call it a four, because I did really enjoy it, just with some reservations.