As someone who has read this story since she was a teenager, I will say that for a vampire story centered around family love and curses, this isn't so bad! While I can understand that some may find this manga to be on the slow side, if you can handle the pace, then I'd say that it's worth the read. Plus, I love beautifully crafted stories centered around sibling relationships! They touch my heart like no other types of stories have done. :D
I'm so sorry for Yaegashi, though! It's not her fault that her model happens to be cursed with vampiric abilities. :(
All in all, even after all these years, I find this story to be very enjoyable! If only the anime could do this story better justice. The artwork is especially well done. I hope to finally find and finish reading the other volumes, if I can! :)