Tony,
My truck came w/the BFG Rugged Trails, took them off at 28k (I'm anal about tires) and I plan to sell them to a friend who has 36k on his set and expects to take them through the Winter to about 40k - 45k. My guess is that the stock BFG would easily last for 35k - 40k "safely" but previous Members were correct, they are NOT Off-Road tires, just an aggressive "all-season" road tire.
I just changed them over before Hunting Season (I see a fair amount of mud in/out of camp) and bought new BFG All-Terrains, 285's. They are my "favorite" tire, had them on my last three trucks and usually get 30k - 35k "good" miles out of them. You can not find a "good" off-road tire that will last more then 35k miles ...
Michelins are an excellent "on-road", high mileage, virtually no-defect tire and yes, they own BFG. I also second "jsimpson" in his second choice for Cooper's, they are ... I believe the last American Made tire and I have had several sets of those, have two sets now on two other vehicles (snow tires)!
Oh, the BFG tires are NOT cheap so plan on a dent in the bank account and they are sold like Saturns, your best deal (which is still ridiculous) can't be beat by anyone as they have a bottom line price. You DO get what you pay for!