i bought the $45 puregear tempered screen protector from t-mobile store, and it seems pretty good so far. it works good with a case. its short on the edges to allow the case to fit nice. using a incipio dualpro case.
if you werent using a case, this might not be the best protector since it doesnt go to the edges.
EDIT:
after using this for a bit, there is a weird effect between the glass and protector. and when you press on the glass, it moves around and changes. i'm assuming the protector is a floating style, and creates a strange behavior between the protector and screen.