I'd probably vote gasser. Cheaper, pretty damn reliable, gutless wonders.
That being said I have a diesel and love it. I got it for sole purpose of hauling crawler and old lady's horse trailer. The house trailer evolved from 2 horse bumper pull to a 4 horse, 20' gooseneck. My beater light weight 20' flatbed got canned and I have a 25' tandem dually that weights 6500# empty. I haul a lot of hay and whatever else i can as a side source of spending money now. If I had gotten a gasser to fulfill what I originally wanted a full size rig for, I wouldn't be happy with it anymore.
If you think you will never do anymore with truck than you are saying you will and you like to pinch pennies, get gas. But if there is a chance you will go bigger toy hauler/use it way more often in the future. Get a diesel.
