Actually, I have never had any of my rifles adjusted for length. I don't know if this is good or bad, but it has just never seemed to bother me.
On the other hand, I have Beretta Xtrema Shotgun that just seems to be too dang long. I think that's because the special recoil pad on that gun seems to be about 2" or so (or at least it feels that way.) As such, I was seriously considering having the LOP shortened on that gun, but I'm not sure I can because it is a synthetic realtree camo stock.
Zachary