I shoot a sleeved William Powell and it is a lovely 16GA gun. If you stop and think about it, many guns today are built on mono-block actions and that is basically sleeved, so done properly I see no problems at all. I try to shoot low pressure loads in all of my guns just because I don't like recoil and the light guns I shoot don't deserve the pounding the high pressure loads put out. Besides, I have found the low pressure loads pattern better and kill just as well. I've never heard a grouse complain.
