Are definitely a major factor. Certain vehicles just have crappy brakes, read here
http://www.raceshopper.com/brake_problems.shtml I had a '94 Explorer that was my wifes truck. She is NOT EASY on brakes (or much else). The best I ever got for brake life on the Explorer was 15k with the Performance Friction Carbon Metallics. In 6 years I went through 2 sets of rotors (all cracked!!!) and 5 sets of pads, THEN my tranny went with 100K, and the radiator, and belt tensioner, and the tranny again (AAMCO SUCKS!!!!) the sunroof started to leak, more noise from the tranny, 4 major safety issue recalls.
Then I bought the Sequoia same driver (still not very gentle), 1st brakes 23k (pads only) rotors still look good, faulty oil pressure sender (known TSB). Thats it for issues (so far, keep fingers crossed)
Buy the Double Cab and be confident you did the right thing.