Any time I push the 124gr 9mm xtp over 1250 fps it has jacket separation and frags does the .40 do better at higher speeds? I also live in iowa and it torques me that I can't hunt with my 9 but anything higher is ok.
from the rather informal bullet testing i have done (lined up milk jugs) the XTP's have held up very well. from a 4.49" barrel i am pushing a 180gr XTP around 1050-1075fps with a max charge of powerpistol. weight retention is almost always 95% or better, expansion is more than adequate, penetration is very good, accuracy is steller, and they very seldom lose their jacket and i have never had one frag on me. had one lose a petal once or twice but they hold together really good. they are all i will use in a handgun for hunting.
all that said, when i used a .40 for deer hunting it was only ever used as a finisher. i would not have hesitated to take a shot if it was within about 30 yards or so but i never got the chance. when i carried it, it was because it was all i had. i have since upgraded to a .44 mag and am very pleased with its performance; both accuracy and effect on deer.