My only concern is my driving is mostly short city drives. I'm sure longer highway drives would be better for the LZO. The fuel cost in my area, Diesel and premium are pretty close in price. Def just adds more cost to the LZO. My 23 Denali 5.3 is a great vehicle. I should just keep it but I get bored very easily with my vehicles. I have an oil change due in a couple weeks with too many decisions to make with these engines. This wouldn't be the first time I left for an oil change only to go back to the dealer with my title and a check, then drove home later with a new truck, Decisions decisions.