Mine is off because of space.

I was going to try to fit it; maybe even get some pro to relocate it for me, but I prefer to spend the money to do some suspension work.

If I have money when I'm done with the speed and handling, I would definately put A/C on.

I would never remove A/C for weight unless it was strickly a race car -- Even on my weekend driver -- I still like the A/C in.