Have you handled both? The Kimber Montana feels like a club to me. Unbalanced and a really messed up fore-end curvature.
I went to the gun shop specifically to buy a Kimber until I held one. I ended up with the Mark V Ultra-Lightweight. Beautifully balanced, 24" barrel.... I have done very little load development thus far. But 100 gr. TTSXes over 51.0 gr of 4350 prints groups that can be covered by quarter (and often much smaller.......operator incompetence, no doubt) with boring regularity.
I saw a Montana once,please tell me more...................