Got them as second tires for the magnesium wheels maybe 15 months ago.
Huge weight difference:
Street Alum Trigos (chrome plated) w GY Eagle GTII 62 lbs:
Track Magnesium rims w GY Eagle "Sports Car Special" slicks 42 lbs:
Saved 20 lbs per corner on rear! Guessing at least 15 lbs front...total 70 lbs lighter.