My Pro Line is on 53 mhz AM. It is not narrow banded, but is not required to be because of the freq band I'm flying on. It was completely checked out and tuned by Tony Stillman at Radio South a few years ago and hasn't missed a beat since. Back in the day, there were only a few 72 mhz frequencies and the 27 mhz band was considered almost useless for R/C aircraft . The 6 meter band was a way to get more flying time with less worry about being shot down. I studied hard and took the test, code and all, but have never regretted it. Almost no one flies on 53 any more, so I can go to the local field and it's like having 2.4 ghz! Biggest problem with flying the Pro Line is that it uses "negative pulse" servos (virtually every other radio made is positive pulse), so I can't use modern servos. Those old PLS-15's are really slow! Also, there aren't many service centers that can or will work on them anymore (Radio South is the only one I actually know of).