Bored throttle body is good, I am rocking a cherrybomb pro, I like it, but the exhaust tube rustys sells is shameful at best fitments wise. K&N is no good for dusty environments, might as well get a nicer drop in filter for the stock box. TB spacer is a waste of money.
So I wouldn't get the package. I would get a good bored TB from www.jeepersandcreepers.com
, and get a cherrybomb or other muffler and have an exhaust shop bend you tailpipe.. Then get a higher quality filter (if you want) for the stock air-box.
Most of the $$ from that kit is probably for the throttle body. From stroked jeep you get a core charge back so its only $90.00 in the end. Or you can get a brand new 62mm body from JandC for 175.