Originally Posted by
Ramsay Snow
Rai is Kindt's best book, in my opinion. Slightly flawed, but an excellent read. If you find the deluxe hardcover (or have to resort to the TPBs), go for it. Cool stuff with a strong manga/anime feel.....And for the record, I'm not a Kindt fanboy. I like his work on Divinity (a good set of limited series which could be better), while I didn't care for Unity nor Ninjak at all.
As for your question about 4001 AD, as another poster said, you do need to read Rai first. 4001 AD is essentially an event which Rai leads into (and I believe the 4001 AD deluxe hardcover has issues 13-16 of Rai, although those are origin issues)