They are different Jeeps for sure. I miss the ease of working on my TJ, especially with the electronics difference regarding the canbus, but the JKU is growing on me in terms of room inside and a smooth drive. I can't say I don't enjoy cruising at 75mph without noticing, in the TJ I would be locked into 3rd for the power to keep that speed. You will have to get used to the length probably, I still have to watch for the right rear on turns, I was spoiled by the short wheel base of the TJ.
2013 JKU Sport, billet, auto, 3.73, LSD, 315/75/16 Duratracs on MB 72, 10A springs, Bushwacker flatties
Sold - 2005 TJ, red, auto, 3.73, 33" Duratracs, 4" lift
Ice storm casualty in 2007 - 2003 TJ, green, auto, 3.73, 33" Duratracs, 4" lift