I love my heated seat, mirrors, power windows (I'm really not rolling over the seat and leaning across to roll the back window on the passenger side down lol). I love my navigation, I love my push button 4x4 (getting out in a sleet storm to lock hubs may make you a man, but it's not very fun lol), I wish I had a heated wheel.
All in all, my 2500HD is easily twice as comfortable to drive as the K2500 it replaced, which was better in nearly every way than the K20 it replaced. The main thing that bums me out is the big block is dead, and has been for quite awhile. I drove a 16 2500HD around for a weekend last summer, and the 6.0 just couldn't compare.