If you're not planning on running the OEM tires then it's probably pointless even at that price.
You'd have to trash 2 wheels to get to the point where that makes much sense.
A few people have claimed they've trashed enough tires/wheels where it is worth it, but you'd probably be better off just getting a Tire Rack road hazard warranty on your new tires for under $100.
Current: '15 M235i Vert
Previous: '13 335i, '08 TL-S, '00 Corvette