I've been running what I call my Frankenquark for a while now. It originally had a bunch of heat sinks on it but I found they were not necessary.
It always ran very cool but the caps would always get very hot as high as 200 f. Well after blowing a few caps I decided to try the sky extra cap idea. So far so good. The piece of angle gets 105 f directly over the fets and were the two pieces of angle overlap and bolt to the chassis they got up to 145 f. I thought that was a little odd. I thought the angle directly over the fets would be the hottest area? The wires and the area were the caps are soldered to the wires also got up to 145 f. This is without a fan in a crt geared 15/46 with big tires driven very hard for three straight sets of orion 4800 4s lipo packs (about 40-45 minutes of continuous racing).