4" lift + 1.5" BL or 6" lift?

Working on getting a plan together for the 2013 RCSB I picked up last week. I want this one sitting higher than my 2012 CC (leveled plus 1.5" BL) but I'm not sure if there is an advantage either way, hoping for some expert opinions.

-Option one would be a 4" suspension lift coupled with a 1.5" body lift and Bil 5100's at 2.8".

-Option two would be a 6" lift and Bil 1500's at whatever would be needed to level.

I know Superlift does not recommend their 6" on a reg cab short bed due to rear drive line vibrations. I haven't seen this issue mentioned by the other lift manufacturers. Would there be a benefit to one option over the other besides the 1/2" difference in height? I'd prefer to go a bit higher to accommodate 37's at some point (maybe, I have 3.55 gears and a 6 speed) but I'm thinking I could fit them with either option?

I know Superlift does not recommend their 6" on a reg cab short bed due to rear drive line vibrations. I haven't seen this issue mentioned by the other lift manufacturers. Would there be a benefit to one option over the other besides the 1/2" difference in height? I'd prefer to go a bit higher to accommodate 37's at some point (maybe, I have 3.55 gears and a 6 speed) but I'm thinking I could fit them with either option?[/QUOTE]

I ended up going with a 6" BDS Lift 6 and put my bilsteins up one notch to make it level. My truck is a Quad Cab so I did not have to worry about the driveline vibration issue. I saw a post from another member recently who installed the 6" BDS lift on a regular cab short bed and he did experience Driveline vibration. Last I heard he hadn't got it figured out yet. I'm not sure why other manufacturers don't mention the vibration issue but I would definitely check into it throughy before I made a decision.