chain rings need to have the same BCD and the same number of bolts. most mountain stuff is 4 bolt, most road stuff is 5 bolt. ok, the SLX M660 is 104mm 4-bolt. Deore M590 is too. so yes, they'll fit.

next time spend more time on the big ring (with correspondingly larger sprockets in back), and ALL your gears (and chain) will last longer. keep your chain clean and lubed, and your chainrings and sprockets and chain will last longer, too.