i play heads up all the time on party poker. i tried the hyper turbos on stars and won 8 in a row the other day and then lost 6. but heads up sit n gos, the regular ones are what i play more than any other game. just be aggressive and don't be afraid to make a big bluff but only if it makes sense in comparison with the board obviously. and think a LOT less about your hand and more about your opponents.