R1.1 is the version I run here, works great, supports my hardware without fart arsing around.
R1.2.0 beta versions I played with were very promising, never played with 1.2.1.
BeOS was nice, but with the 1.x series, Zeta moved from being "BeOS with hacks" into something with it's own distinct charactor.
To call the the latest versions that would be to do Zeta a grave disservice imho.