The Reality Dysfunction was the first I would say 'real' SF book I read. I say 'real' in the sense that my SF reading up to that point was really more 'fantasy in space' or written so long ago the technology of today and our current knowledge sort of make it less interesting to enjoy. This was the first time I encountered the sort of hard sci-fi as well as space opera book.
Anyway, from a heavy fantasy reader, this book blew my mind and jump started me onto reading all the SF I'd been missing out on all these years. When I finished the series, I had a few complaints and really didn't like the whole possessed plot which is kind of silly since that's the whole point of the books. I just liked reading about the space ships, the different worlds, the battles all the weird aliens and technology.
I've went on to re-read most of PFH's books several times but never TND. I wanted to enjoy my memories of it and not think about the 'space zombies' aspect. But after almost 10 years I thought I'd give it another go after reading after so many other books and seeing if it holds up.
I have to say I enjoyed it even more the second time. I appreciated the possessed plot more and was more sympathetic to them. With so much time since reading the books, I forgot a lot of the little things happening which added a richness to the story. Even the ending which I remembered as quite jarring didn't bother me the second time. I was only sad it ended and we'll never see what is to come next.
I'm looking forward to reading them again in another 10 years
p.s. Gods, those were huge novels.