I just got my NHF800 two months ago, so it's way too early for me to even consider a new MD unit. The 800 fits my needs (analog recording, portable listening) quite well and I think it'll be a while before I want something else.
I couldn't find any 1GB discs locally, and the best deal (including shipping) from a reputable site I found was at B&H. I bought a quantity of five and received them in a 5-pack box. Item Link
Just to throw another hat into the ring: I got an NHF800 unit for Christmas and have successfully uploaded & converted four 50+ minute PCM recordings so far with SonicStage 2.3 and MarcNet's utility (running Windows XP). I haven't yet tested Sony's WAV converter.