Fallout 2 Enclave, nothing is comparable in coolness and protection. T-45d is junk, T51b isn't bad but the appearance is so bulky, Enclave F2 style is large by sleek and awesome.
I'm not a big fan of Power armour particularly with FWE, Combat armour is a lot more effective imo (Reilley's Rangers variant even more so) it has decent protection and you don't suffer to much of a speed hit.