I just want to leave a bit of feedback on here for anyone looking for a radio system quick.
I decided to spring for a radio system finally, and settled on the Club Racing Radios Budget 5-watt system. I purchased the system and struggled to get it to work, no matter what we tried. So I called Mark (the owner) and asked him about it. We went thru each part number of each cable to verify I had the right ones. We found I had an incorrect cable, so he just sent me the new one, drop-shipped overnight to the track. Unfortunately, that still did not help. I decided just to send it all back for him to diagnose, figuring I was just screwing something up somehow.
After a day or so, Mark calls me & says he could not get it to work no matter what he did either, and that he was out of stock some stuff to replace it. So he decided to just give me a free upgrade to the IMSA Pro system. Not only that, but he then sent me back the original radios which do work on their own, just not with the headset stuff. He worked with me on an off-weekend at home to get things measured & custom cut to fit in my car, and gave me a ton of info on how to get the best performance out of it. As soon as I got it hooked up per his instructions, things worked perfectly.
So anyway, if you are looking at getting radios for your car, absolutely give Mark a call. I see Dave Weitzenhof has a post here about CRR too, so this doesn't appear to be a one-off lucky interaction.
http://clubracingradios.com/