On that I can agree with you it's the best interface, but lately it's been sinning a lot in the reward plans, before it had a much better freeroll affinity than today, and its rewards were better, including the challenges and today everything went bad.
Pokerstars is good, but i like 888 poker even more. 888 has more regular freerolls and promotional freerolls(The Grand Adventure) + CC daily freerolls. Additionally they added promotion for Cashgames (cardstrike). Deposite and Withdrawl(1-2 Business days) is super fast (1-2 Business days). If you have the option in your country, try out 888 as well. More freerolls winning equals bigger bankroll ...