I've just started on Absolute Poker from a long time on Pokeroom and Pokerstars and I must say that the software and the 200bb stacks do take a while to get used to ( i still sit with 100bb for what it's worth) but I have not had any problems with the site in general or the
rakeback.
Once you customise the table and get the HUD sorted then the softness of the players more than make up for any short comings in other departments.
The only downside I can see intially is the bonus, while sizeable, is very hard to clear at the lower limits ( 25c - 50c ) and the rakeback is from your rake minus the bad beat jackpot which can be a good percentage.
All things aside, I would say that if you wanted to build a bankroll at 25c-50c and 50c-$1 then Absolute, with it's rakeback and very soft opposition is a much more attractive site than Pokerstars of Full Tilit.