Fluidyne radiators have long been the standard all other aftermarket Supra radiators have been judged against. High quality welds and brilliant polish allow this reliability modification to score some show points too. I've had mine for 4 years, and since installing it have not had any more issues with a creeping temperature gauge in extreme conditions (long uphill grades in hot weather, Central California track days, etc).
MK3 Fluidyne: $415
MK4 Fluidyne: $450