I've never shot or owned a Wilson but I do have a LB PII. The slide to frame fit is good but not super tight. It's a pleasure to shoot and in the right hands (my 14 year old son shoots 1-2" groups at 15 yards freehand) is extremely accurate. The fit of the gun is top notch--the barrel bushing is snug but not tight, the ambi safety is fitted perfectly and engages positively, the beavertail is blended to the frame, the frontstrap checkering is clean. The finish is good, but like all blued finishes it shows holster wear. Contrary to what others think, my experience with Les has been very positive. For example, when the PII didn't lock back on the last round, Les promptly sent me a new slide stop--no questions asked. When the front pin on the Bomar knockoffs broke, I had one in two days.
I have only a few criticisms of the PII. New, the trigger pull was about 5 1/2 pounds--way too heavy for a semi-production gun. It took some tinkering to get it down to 3.5 lbs. Secondly, the Bomar knockoffs are inferior to the real thing. I ended up putting on real Bomars.
I think the PII is the best value in the high end 1911 market. What I like is its completeness. Everything you'd want is there-- ambi safety, checkering, Bomar style sights, tool steel lockworks, wood grips, etc. I can't see spending $1600 on a gun and then spending another $100 to get ambi safety's, etc.
I've heard rumors (if I'm wrong, please correct me) that Wilson uses MIM lockworks on some of their guns. If that's true, it's outrageous to charge that kind of money and not use tool steel. While they are nice guns, I think that Wilson's are over-priced for what is essentially an upgraded Kimber (slide and frame are Jericho). Anyway, I'm sure that most Wilson owners are just as happy with their guns.