Originally Posted by WhyFi

I'd bet that most SP cleats are replaced when the plate and screws securing the retaining clip are ground down through walking as opposed to being worn out through use (un/clipping and pedaling). If you're not walking around on the metal plate/screws (by using cafe covers, keep on covers, SP's new walkable cleats, etc) they'll last a long, long time.

Also, I think that the maintenance of SP is often overstated and mostly by people that don't use them. A squeeze of grease in the pedals once in a while and a puff of dry lube on the cleats is easily and quickly done.