I have one on each of my 503f's. I love them. I do not ride the trails that much, but when I do it really helps. It also is very nice for getting up to the powder or whatever. My friends without them ride my machine and comment how stable it is. I would recommend trying it.
probly the worst thing adb did other than not making the 503 hawk anymore...ill give you 25.00 plus shipping for it...let me know where to send payment