I tried going through the process of unsubscribing and opting out of everything I could find, and while it slowed for a few weeks, it eventually picked up again (just like email spam, when you make use of "opt out" options). J. Crew were the most damnably aggressive spammers...after repeated attempts to opt out, they were still sending me two catalogs a week. I'll never make the mistake of buying someone a gift from J. Crew again.
Anyway, I needed a mail forwarding service, anyway, since moving into an RV, but this turned out to be an awesome bonus and I wish I'd set it up years ago. I will never be without a mail forwarding service again...for less than $20/month it's just too convenient to have someone else sort and scan my mail, and get rid of the garbage.