In general, a more useful sequence is:
1) Ask
2) Buy
... if you're looking for advice, not the other way around.
Since you asked for feedback... I wouldn't spend the money it takes to get a Wilson 870 as long as I could get a NIB 870P for the same or less money, or a good used LE trade-in 870P for even less. But that's just me. I've been shooting 870s for thirty-something years, and have yet to buy a new one. I ordered a new 870P for myself for a 50th birthday present, but the distributor shipped the wrong model and I sent it back and let the idea go.
By "Class 3" I'd guess you mean it's a SBS or NFA model. That doesn't really trip my trigger either, I see no need for paying $200 extra for a few inches less barrel plus putting up with the other NFA hassles. I can do fine with an 18" to 18.5" barrel, the 'house guns' here are right at 37" long overall with a 12.5" LOP stock and an 18" barrel. That's plenty handy, and my 5'4" wife can handle 'em just fine too.
If you like it, you can afford it and you can use it well, then it's fine for your needs. Nothing wrong with getting what you want, that's for sure. But it's too much sugar for a cent for me.
Enjoy it and Stay Safe,
lpl (and if you ever have to use it, try not to worry about what happens to it while it's in the evidence locker)