STone,
I dont know why but I havent found almost ANY difference in the $25 and $50 games. When I started, I was in damned losing streak that was meant to be recorded or something...for STUDY!. WOW. I remember it and I feel bad. I knew the games were going to be great because most players couldnt stop calling my huge bets wit their gutshot-always hitting str8 draw.
The only place that you shouldnot be around in terms of game quality is Absolute Poker. OMG. I have named it THE ROCK GARDEN!!! I guess they have so many bonuses it´s worth trying it, and anyway, for some reason, there is where I win the most along with Bodog.
Lately I have been killing the $50 games. As I told you the only difference I find is that you can find a couple decent-good players sometimes. But ina medium poker room like bodog or AP, there is probably 4-5 of them. So that´s not so bad.
I went to Prima to clear the expekt bonus and in 900 hands I did 102. I didnt notice any difference. They were maybe a little more aggressive than most sites, but that´s basically it. I dont understand how you find the expekt software so good, compared to Party´s. I think they are both pretty standard. Nothing extraordinary, but the party´s software is way more fast,and you play a fe more hands/hr.
If you are having problems with Prima, I think my recomendation would be Bodog. That is a damned fish tank. A+ there. No PT support so F-- there. The gameplay is very lmuch like party, without the laggy factor

.
They have also a great cashout system. My last cashout was processed in about 4 hours, and all other are done in less than 24 hours, including weekends, something they dont do at expekt.
There are many options. I havent tried stars at the $50 tables, because they are tight (most people say) and good. I had heard that also of UB but that is just a lie! That s another fish tank. The only place where the games get really boring and tight is AP. Also, you can find a few good players there.
I just hope the transition to the $100 tables be sooo easy as this one has been. UB or bodog are your best options.
Good luck, my friend.