Bob:
I think the point was that if you put together an AR yourself or had someone put together a custom AR for you, you don't get the security of a factory warranty.
Yes Wilsons are pricey but your point doesn't consider that yes, a trigger and hammer group will cost $200 but then it must also be properly installed and Wilsons, as I indicated above, provide a tad more than just a warrantee and trigger/hammer group (match fluted bbl, brake, forged upper/lowers, free floated alum handguard, houge grip, premium parts all profesionally fitted and guarenteed). As for finishes, yes any finish may very well get scratched, but I don't think future wear or scuffing is necessarily the major consideration when choosing a finish.
At $1,600.00 they sound pricy but my point being that when you consider the entire package, its not exsessive. You may be able to purchase two stock ars for the same price, but once you begin the "tricking" process you might even end up short and without a warrenty or service dept to turn to.
They may not make sense to you or others who are capable smiths, but they sure fit a niche for those want a custom tactical a factory warrantee and service.