Not sure how well they cool (I use the MP clutch fan kit), but they're not good for performance: https://allcarvideos.net/2017/05/01/cooling-fan-shoot-out-engine-masters-ep-20-2/

2021 Challenger 6.4L Scat Pack 1320
100% stock: 1.680, 11.894 at 113.75 (DA 175 ft)
weight reduction, wheels, tires, Hellcat air box: 1.661, 11.686 at 115.97 (DA 710 ft)

1973 Challenger 452 ci street/strip [2008]
pump gas, DOT radials: 1.454, 10.523 at 126.44 (DA 514 ft)