I loved this book! If you are interested, there is a website dedicated to Ken Grimwood at: http://wganoe.home.mchsi.com/index.html
I read this when it first came out in '87 and I loved it too. Thanks for the link. I didn't know Grimwood was deceased. I was so surprised that I really never saw more of his work since Replay was so good. Now I know why. I wonder how far he got on his sequel to Replay. I'm not sure I would have wanted a sequel - it was great all by itself. As a librarian, I have talked that book off the shelf and into the hands of readers many times. My greatest fear is that someone would weed it out of the collection! Thanks again for the update.
It's written for adults, but not at too literary a level. It is one of the best fantasy novels ever written.
For adults... no. It's easily understood by high schoolers. There's a lot of sex and some drug use, however, which means that some parents might not approve of it for their kids.