I have both the BST carbon wheels & Forged Magnesium Marchesinis - I am pushing near 600 hp and would recommend either.
Marchesini also make a forged aluminum wheel which looks very similiar to Magnesium
Be careful on the Performance Machine stuff - Most of their wheels are heavier than stock and some models do not have cush drives
Might want to also check out the OZ Aluminum wheel - I've heard nothing but good about them
FYI - The absolute strongest magnesium wheel is the Marvic - KILLER wheel - Most of the ProStar guys all run it - I have had them myself - Excellent wheel