The part numbers on realoem.com show the rear bar is the same as an i. Still need to check bushings, brackets, and endlinks to make sure they are the same parts numbers.
In other news, I did my front sway bar end links last night. It's pretty easy if you have the right tools. You need to jack up the front end (take off both wheels) and use a T-30 torx bit on a socket to hold the bolt stationary while you spin the nut with a 16mm wrench. The closed end on a standard craftsman wrench worked well but those ratcheting type wrenches are too big (which would have made it a 5 minute job each side).
I bought the OEM style lemfoerder one from pelicanparts.com. It made a noticeable difference and for $60 its a no-brainer. The suspension is much quieter now and I could be making this up, but turn-in feels tightened up.
I have 87k on my xi.