Easily the best upgrade money I ever spent on a vehicle.
Replaced entire factory worn out leather interior in my wife's Montero Sport with a Katzin leather kit. Better material, sewn perfectly to factory patterns, better padding, perfect fit. Even had the seat belt pockets, and child safety seat anchor ports sewn into the middle row seating.
I used Affordable Auto Leather in Arizona and had a local shop install the kit, although I probably could have done it myself. Affordable Auto Leather-John Huey, Katzkin reseller, popular on the Tacoma forums. Affordable Auto Leather-Katzkin