Sundance,
When I shoot a revolver, I tend to grip the gun very tightly in anticipation of a big boom from a relatively small gun, like a .38 with +p for example. Since I do the same thing with my Pocket Nine this tends to negate the heavier trigger pull. The trigger pull is not as bad, for example, as a kel tec which is both heavy and long or a sigma which is heavy, long and gritty. Mine is comparable to my Kahr MK40 in weight.
You are right, Colt was in fact sued by Kahr and Kahr prevailed. If you take a look at any of the Kahr series they have an offset barrel lug. This allows for a tighter fit with the trigger mechanism and a skinnier pistol with a lower barrel mount. The Pony and the Pocket Nine were all affected. I don't know if the Defender has this configuration or not.
I had a Kahr P9 which I really liked but sold to finance the Pocket Nine which was just a bit smaller and the layout made for easier carry.
The MK9 is a great gun, I have an MK40 which is a keeper for me. But the MK9 weighs more, right? Like another half a pound I think?
I had a Pearce floor plate on my P9 and have them on my MK40 too. For me, they make these small guns controllable. I could handle the 9mm without one, but the 40 is unmanageable without the floor plate.
When Kahr comes out with the MP9, I will be first in line to get one.