If it was me, and obviously it isn't in this instance, I would go with the 17's. I've had 17's on my truck since I got it, and haven't ever had a flat tire. Aired down a lot when off road. Climbed all over the mountains in Colorado. Blasted though the snow in Michigan. I was alway glad to have that extra rubber to keep from worrying about the tires. Plus, tires are easy to buy in that size and and cheaper, too. Just my $.02.....
This is true and I really would like Method NVs. I just messaged discount tire to see if they can get nvs in 17" and change the tires to 315/70/17s. Plus if I go this route I won't have to worry about my speedo being off.