For me it's not that the 327's stats don't say it's a good SD round it's just that it's not tested in the field like 9mm, 40, 45, 357, 38 special. I'd take any of those over the 327 for SD if I had a choice. I'm not comfortable being the guinea pig for testing new SD rounds. I might do that with a new deer hunting caliber but not with my or my loved ones lives.There is a big difference in recoil if you shoot .327 and .357 from the same gun (model), i.e. Ruger LCX. Significantly less recoil from the .327...plus, 6 vs 5 rounds in .327 vs .357.
I think an 'extra' round outweighs the advantage of an additional .045 increase in diameter (.357 vs .312) per bullet.
That said, I think a six-shot revolver in.32 Mag is a good package...and one in .327 Mag is great. The Ruger LRX is light. There are other offerings by S&W and other makers that weigh more.