I am a very happy user of Easynews $10 US (gotta love the weak dollar) a month for 10 GIGS of download.
The retention is about 35 - 40 Days and you gigs each month roll over each month. Ive currently got about 30 left in my GIG bank so it's plenty enough for me.
The best thing about easynews is the the ability to search all newsgroups with a very good search page. Select the type of file (parity, binary, MP3, video, Image etc), date posted, minimum file size, etc.
I have never got into the peer to peer stuff just to slow, but with easynews I can get home from work, search for a DIVX, download it and watch it before 10 PM
Easynews is also HTML/Webbased are they all like that?