I’ve done well with PartyPoker.com and like them very much.
The only other poker program I’ve really seen any action from has been Golden Palace Poker through CasinoBlasters. That one’s been good to me too.
I’ve had good luck receiving communications back from the folks at PartyPoker, so it’s disheartening to hear about your experience. I’d definitely follow up with them in a more-or-less stern fashion regarding their lack of response.