Did not notice any difference really in the groups for all 4 loads. All were quite adequate. If I had to pick, velocity wise, I'd probably go with 8.5g CFE Pistol to match my 7.0g Green Dot load. or 9.0g CFE Pistol to match my 8.5g Unique load.
For a comparison I shot some 8.5g of 20/28 under 250g RNFP for 1014fps.
Would I use CFE Pistol for .45 Colt.? Yes I would if I had to (why I tested with it). Not a bad powder at all.... I just prefer Green Dot right now for my goto loads and just bought another 8# of GD for that reason.
If you want to use heavy loads, I suggest W296/H110 with bullets weighting 240 to 260 gr, Federal large pistol magnum primers. Apply a heavy crimp. As for the weight of powder, I would use loads in the 25 to 27 gr. Being that H110 and W296 are the same powder, the load information for these powders are interchangeable. Again don't forget the heavy rolled crimp.
I to shoot the Keith 255 and the same gas checked bullet with AA # 9 at 17 grs. out of a Bisley 5.5 and Winchester trapper. Its my standard load for both. Have take a couple of norther whitetails with the load out of the Bisley. Both guns shoot the plain base better then the gas checked.