Oh, to further answer the original poster -- no problems with installation, at least on a 300m. You need to find the speed sensor wire to enable the nav, though, so I took it to a pro shop. $60 install. Speed sensor wire is the only possible complication, no idea if that's easy to find on an Xfire (haven't pulled the trigger on one yet, but will very soon). JVC sells an add-on unit for cars without the speed sensor wire or ones where the wire can't be readily tapped. Sits in the wheelwheel or something. Kind of pricey.