I also did a rear brake job (calipers, rotors and pads) a couple weekends ago and can confirm the remanufactured calipers from NAPA were exactly what came off the truck. Must be why the core is $85 on a $60 caliper. They know they are getting a good shell back.
As for improvements, its night and day. I got rid of my bumper dive on hard stops. I think a lot of people that have that issue and chaulk it up to worn springs should do brakes first and bleed the LSP valve.
C-Yeti
Where able to re-mount the Factory stone guards?
I am doing my rear brakes and e-brakes and opted to requild the originals.. I was very tempted to go Napa.
There is a recent post of a set of rear caliper that were powercoated and they looked really nice..