In my opinion, 888poker is the best for those who are just starting to play poker, for those players who don't know how to play well and constantly play freerolls, 888 is the best option. Pokerstars has a better interface and more tournaments and more online players at any time of the day. But PokerStars doesn't have a lot of freerolls and there are quite a few good players on PokerStars. So if I was just starting to play poker, I would choose 888poker at first and then when I get a lot of experience and skills, I would switch to PokerStars.