Good to see you back, Bob. How ya been?
To the OP....
I'm not the biggest fan of Wilson,Vang,etc. A cognizant 870 owner can do most of the stuff him/herself. Forcing cones, triggers and backboring are the exceptions.
Don't get me wrong. These are reputable firms offering good services and parts. However, what an 870 "Makeover" costs from them will buy a lot of ammo and range time.
And,finally, a checkbook never can substitute for expertise. Get good with your present, unaltered shotgun before spending much on tweaks...