I installed this yesterday in my 07 X
I am not sure on the warranty. It's a mopar part, so I don't think it should void it.
After installing, it worked without a problem. No need for a trip to the dealer.
Here is a decent write up of the install:
A quick search on this forum showed no results for a write up of the install.
They are not kidding when they say use a "stubby" screwdriver. I didn't have one and ended up destroying the plastic cover (which is replaced with the install anyway) to get at the airbag clips.