RE: Whats been the biggest effect of 2.4 ghz
Not all 2.4 rx's are 100 dollars. Spektrum makes a perfectly good 6 channel full capacity rx for only 79 bucks, which can usually be gotten for 69 bucks if you look around on the internet. That's not bad when compared to PCM rx's, which is really what we are comparing here as far as quality and available options.
I think a benefit is not worrying about channels and who's in the airnot only when you are ready to fly, but also when you are working in the pits trying to get ready to fly. Gone are the days of waiting on a pin just to get your plane set up and ready to take off. Gone are the days of waiting on the pin for 10 minutes while someone sets their plane up, adjusts the carb, etc, refuels, and then flies for 15 minutes before you can get your pin back. Gone are the days (with spektrum) of choosing the wrong model in your computer radio.
I love my 2.4.
Granted, I still have over 1/2 of my planes on 72 because I'm accumulating rx's slowly, but surely!