Oldelk - I too have had good luck with the Win Supreme in both the 12 and the 20 ga. (Both Rem 870s). I shoot 4s or 5s out of the 12 and 5s out of the 20.
Another good load that I've used is Federal Premium 3 1/2" in 4s & 5s. And although I killed a few turkey with them they are really stout loads. Pattering my shotgun with these wasn't fun.