I liked the premise. The progression of events were a bit of a stretch at times.
Unfortunately, her characters lacked a lot of believability. The hero is supposed to be super-smart in various ways (reasoning, memory, speaks several languages, etc.). He could recall verbatim things he has heard or read once, even years later. He still doesn't manage to say the most common everyday terms correctly by the end of the book. It was really irritating. He also told everyone, not just the heroine or his teammates, that he had time-traveled without figuring out that it could cause problems.
The heroine wasn't a much better.
The writer did emotionally engage the characters so I did care about them.
The writer tries hard to be funny. Ha,ha, ha! The repetitive joke format got old. I did chuckle a bit, though.
In spite of all that, I liked it. A quick read.