I believe STI added an advisory to their website to avoid +P ammo after they ended their relationship with Grand Power.
Regardless, your Grand Power pistol should run any quality factory ammo without fear. Consider this a personal challenge. Go ahead and try to kill one. Get back to us with the results. I think you will be pleased.
Yeah, that was what got my attention. The Grand Power website also warned against firing rounds through the gun that wasn't factory ammo-- although they didn't say anything about higher-pressure "factory" ammo, or +P ammo in general. So, yeah, that's why I was wondering.
I bought my CZ-75 SP01 because it could take almost anything you fed through it-- target ammo, defense loads, high-pressure handloads, etc. It's reliable and ridiculously-accurate without being a "range queen." I am considering the GP K-100 as a lighter-weight carry piece, along with a P-07.