I've been round probably all the pools. I always end up back to either BTCGuild or Eligius. Eligius tends to be my favourite, mostly due to the 0% fees. It's solid as a rock, too.
Thank you very much for the input. Is in not viable to farm solo ? I have a 500gh/s box
Perfectly viable. But you could spend a LONG time to get a block. Or you might get it in an hour. It's a lottery mining solo. That's why pools were set up - so there's lots of miners 'buying tickets' for the lottery and then splitting up the winnings.