I already sold the steel wheels and went back to the factory wheels because of how much they weighed and the fact that they couldn't be balanced.
I figure 3 mpg at 10k a year isn't that much...maybe $250 a year or so in gas. Some of my fuel mileage loss has to be from the switch to the winter fuel.
Part of me says sell the BFG's while they're still new (they have 400 miles or so on them) and they're like new still...and part of me says just keep them. The Uniroyal Laredo Cross Country is a decent-looking tire and it's a lot lighter than the BFG AT...If someone offered me $450 for all 4 new bfg's, I'm pretty sure I'd take it. Although it is a really good tire compared to the stock goodyears...those things couldn't keep traction in the rain let alone the snow.
best highway mileage I got was with my 31x10.50x15 BFG ATs, the stock tires with the Level II package. I hit 21.6 on one of my long distance trips. Most of the time my trips ranged from 18.9-20.1 on highway trips with the ATs. My MTs are another story since they are 33s. Plus I'm sure the 4.10s help for me too.