S&W 642 Airweight with CTC grips (the new rubber ones) -
Don Hume JIT...the laser 'bump' stops just at the top of the leather. The fit is real good.
Ken Null SKR...had to shave just a tiny bit of plastic off to accomodate the bump. Otherwise, no problems.
GALCO SUM158, IWB...bump fits inside the top of the leather, but does not change the fit appreciably.
GALCO SM1583, belt slide...same as above - leather spreads just a tiny bit to accomodate the bump, but fit is still strong.
Uncle Mike's pocket holster...no problems with fit.
Uncle Mike's ankle holster...no problems with fit.
PagerPal...no problem
SmartCarry...no problem
Ruger SP101 2" barrel w/CTC hard plastic grips-
GALCO SCT118...slight spread at mouth but fit is fine.
DeSantis 002 22...slight spread at mouth but fit is fine.
PagerPal...no problem
SmartCarry...no problem
Bianchi Accumold Snap-on Belt Slide...slight spread at mouth but fit is fine.
Those are the holsters I have and the only ones I've tried.
Hope that helps.