I test-drove both and wound up buying the 6-speed... just more fun to me, although heavy traffic tests my patience a bit more now, lol. I don't think you'll see a power difference in the manual vs auto if you get the 4.10 gears, though.
Tyler R. - Ansonia, CT
Silver '12 JKRU
6-speed, soft top, 2.5" TF Lift, 35" Treadwright Guard Dogs, Smittybilt SRC front bumper, Superwinch TS9500 winch, M.O.R.E. oil pan/trans skid, Skid Row exhaust loop skid, Dominion evap relocation,*Smittybilt Oversized Tiire Carrier and Cibie headlights.