Is there any advantage to a T5 over a hex or vice versa?
T5 and Hex are totally diferent (5 edges vs 6 edges) - so the "correct one" is the hex but you can work with a t5 though this will damage the screws. Have a look at this picture from linegear (could not find a picture of a OEM screw this fast):
X-Squared - Nose Bridge Screw
High Quality - Nose Bride Screw for X-SquaredAs you can see the third picture, this screw works for …
www.linegear-japan.com