I clean and lube all my guns (all M&P's), but the M&P22 has an aluminum slide, so I make sure the slide rails and barrel, inside and out, are kept very clean and lubed after every range trip or competitive event. I only shoot Mini-Mags through it, as they are cleaner than the rest.
So far, it seems to be holding up a lot better than the Walther P-22 I had, with the same amount of ammo through it, over 5000. The P-22 has a zinc slide and didn't hold up.