I personally prefer PokerStars.

I haven't played for a year or so on UB, but here's what I noticed:

PS == PokerStars.

PS .01/.02 NL has $5.00 Stacks vs. $2.00 on UB - so if you play tight/solid poker you are rewarded more. PS also has .02/.05 NL which is a more gentle step up than directly to .05/.10 NL.

I found the $1.00 SitnGos on UB to be very frustrating since players just don't care about $1.00.

For some reason I was far more successful on PokerStars $5.50 SitnGos and if I played them along with 1 or 2 small stakes NL games my BR rarely went down.

There are .05/.10 and .10/.20 Limit games on PS in case you ever feel like playing Limit. UB has .01/.02 Limit - which is a waste of time or .10/.25 Limit - which can hurt a $50.00 BR.

UB software was more buggy - don't know if it's improved or not.

If you use PokerTracker - it works a little easier with PockerStars - in UB - you need (or at least you used to need) another application running to read your handhistories or have UB email them to you - which was a nuisance.

The only thing nicer about UB was the miniscreens - although they take some getting used to .

Martin