I do not have experience in other poker sites, but as the system still has its suspicions, it could be that there is some difference yes.
Note that
online poker is governed by computer system to randomly draw cards and the same system used in PokerStar, is not the same in Poker 888 and
partypoker, so it may be that there is some difference in the card in other sites, but of course not I tried the game on other sites I'm not sure if it exists.
I can talk in buy-in levels, in smaller buy-in games it's possible there is a difference in the level of players, because those who play at the lower levels do not have much experience and are always
bluffing and going all in for any card but not cheat the game is even in all situations.