I had one. It was accurate and a pleasure to shoot. Everyone cringed when I'd show them the gun thinking recoil would be nasty. I honestly don't think it is worse than a compact 9mm. Very controllable. Very accurate. Kahr has the shortest slide in height, this allows the grip to be a larger percentage of the overall height of the gun. Here's an example:
With my HK USP Compact, my pinky hangs off about 1/2 way. I can't really get it on there. On the Kahr, which is a shorter pistol - my entire hand can grip it. Yet the gun is shorter. That's because less space is used in the slide area.
Mine was finicky on ammo. Had some failure to go into battery issues. If you check the Kahr Club forum on Glock Talk, they discuss the details of the Kahr 45. Might want to look into that. There have been some reviews and threads on this forum also, consider doing a search. Kahr has corrected this issue with profile of the breech hood.
I got rid of it because it was too large for my tastes. I need something just slightly shorter in the grip area to get away with IWB carry. The Kahr45 was difficult because here in Florida, it is rare when you can wear an outer shirt to hide the buldge. 95% of the year, you wear just 1 shirt, anything more and you are sweating like a pig.
Now, in a smartcarry/thunderwear...it disappears completely, but I don't favor that method of carry. If you are up north and outershirt/jacket wear is very common, this will conceal very well!
Good luck.