I put Hogue Handalls (sp?) on my HK compacts since I first started carrying the HK. They made the grip much more comfortable because they covered the deep "checkering".
The down side was that as they "wear in" they have a tendency to slip, read this as the gun WILL twist in you hand when you shoot. The solution is to replace the Handall at first sign of wear. This is all well and good if you don't mind droping $10 a pop every couple of months BUT there is another problen with slip on grips. Even new ones allow the weapon to "torque twist" if wet, either by perspiration from close body carry or other sources of moisture.
My solution was to do what the Glock Guys are doing;
Loose the Slip Ons and go to an "AGRIP" from Brooks Tactical (www.brookstactical.com). This is a "Stick ON" grip material that does not slip under any circumstances, it actually works just as well wet, so body perspiration and sweaty hands are no longer a problem. I could go on and on but their web site says it all.
Only one drawback, they only make a USP full size at this time so modification is necessary (last time I spoke with them they said they were looking into producing a USP Compact version (they thought the the only differance between USPc and USPf was the length of the grip but after a lengthly call from me they now realize the grip circumferance is significantly different, they're basicly Glock Guys but don't hold that against them)). The installatin of the "oversize" material on the Compact's grip is easially accomplished but requires a bit of trimming, I've done it on two Compacts so far but will replace the work I've done with correctly cut material when available, the Agrip material I have installed looks OK and functions PERFECTLY but I'm fussy and want perfection.
Now, how does it shoot? As advertised! It works great and adds virtually nothing to increasing the size (reade circumferance) to the grip, slip ons add significant grip circumferance (although not excessively so).
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