I use
Newsfeeds and newsbin. Newsbin is great at handling all the servers together and daily download limits. Can't remember the last time I ran out of download credits b/c they have enough good servers. ($160/year)
I tried usenetserver.com for a couple months. I wasn't happy with completion rates at the time. Actually, it was down right terrible right before I jumped. However, the first couple months I had it, I loved it. It may very well be worth the money right now. The particular groups I was hitting, though, were happening towards the end of my membership.