My mom and I shoot together quite a lot. She is fairly thin woman, but not petite. She basically took over my GP100 6". In contrast, I have a 3" SP101, and I have only gotten her to shoot it once. She did not like it, and will not practice with it to try to get better. For reference though, I do load all of our ammo with full-power H110 158gr loads. The 3" is significantly more intimidating to shoot and will give me blisters on long shooting sessions. The GP100 trigger is better in my opinion, but it probably has 4000 rounds through it and who knows how many trigger pulls? The SP101 probably only has 500 rounds through it as I just got it this past year. You can tell the GP100 trigger does seem to simply offer better mechanical advantage, besides grit and spring-wear, but I dry fire it a lot and it has improved somewhat.
I think the GP100 4" or 6" is the way to go.
I think the GP100 4" or 6" is the way to go.