I have 2 KS jug 10 mm saws, and both very very strong stock. One is now ported with Randy's "new recipe" and is even stronger.
I have seen other strong running 044/440s, and not, but I think the KS jugs were just consistently among the strongest running. With a DP muff cover and HD-2 filter (or max flow), they will hang with a lot of 046/460s with the same modifications.
I have also seem some rather anemic 440s out there.
There were Mahle angle fin 10 mm jugs, and angle fin 12 mm jugs also (some of the early ones).
The jugs are likely the biggest reason for any performance difference, but the 10 mm saws also have slightly smaller case volume.