I'm running AR Torq Thrust II's, 17x8's. They have the same as stock 4" BS. I have 255/50's for tires. My drop is 4/6. No problems at all. If you go with a 10" rim out back, I think a 5" BS would work out great. This would look good too, because of the narrower track the rear of our trucks have. This would bring the wheel/tire out 1" farther and match the front.
Only reason I went with 17x8's all the way around is so I can rotate them.