I installed my RE 3.5" superflex kit which came with new lower control arms, springs, sway bar extensions for the rear, disconnects for the front, longer stainless braided brake lines for the front, a Transfer case lowering kit and a rear track bar relocation bracket.
It took me about 6 hours to install it, it was very easy.
You will need to buy long travel shocks, I went with Old Man Emu.
Its recomended that you get an adjustable front track bar so you dont have to drill a hole in the mounting bracket on your axel to relocate the stock track bar. Also upper adjustable rear control arms are recommended to correct your pinion angle.
You dont need an sye and cv driveshaft, but it is also recomended, and you wont have to lower your transfer case.
I did an alignment myself which is fairly simple also.
And yes it will drive much different, mine drives alot stiffer, I like the way it feels though.
here is a good write up on installing this kit: Rubicon Express 3.5" Super Flex Suspension Lift Installation - Jeep TJ