I bought a set for my truck, stock mirrors didn't extend/retract like the newer trucks, plus I broke the plastic that surrounds the knuckles. Bought some off Ebay, they bolted right up, power mirror works great, the bottom mirror is adjustable (stock isnt), only down fall is the aftermarket mirrors vibrate a ton going down the highway.
I still plan on trying to swap the innerds from the stock mirrors to the aftermarkets, just gotta get the motivation up.
I saved about half the money versus buying OEM and I'll deal with the vibrating mirrors!