Seriously, the V10 isn't going to see much of an MPG difference with 4.30's vs. 4.10's.
If you plan on putting bigger tires on it, get the 4.30's.
If you do any stop-and-go driving, the 4.30's will help the city MPGs because they put less of a load on the engine, as long as you can stay out of the go-pedal
And, for the time you'll have the stock tires on it, it won't make a big difference.
Plus, who knows what you'll plan on doing with it later on? An RV might be very attractive after you get used to your new Superduty. Good luck with whatever you choose!
