I think I would make a list of radios that would fit buy the spec sheets. and narrow it down from there because size does mater (lol) in your application. I have the RFX 75 on the back of my radio and yes it will get hot and should be fan cooled. But I love it, however it is stock on my omegaforce S45HP. if not set up right on any radio you will have problems. you need to narrow down by the size of the radios and how many chanels ssb or not. I run a mobil cobra 29 lx for me stock they work great with a tune even better or a mic change I like the road king for noise canceling. and most of the time I olny talk a few miles. When I get closer to home a small 100 watt box does the job.