RE: Radio most used at events?
I inspected planes this summer at the pylon Nats. I would say at about 85% of the planes were Spektrum/JR powered, maybe 13% Futaba, and 2% Hitec.
Spektrum / JR was out first, so I know some of the original futaba pilots switched over before futabas dedicated 2.4 ghz radios were available.
Both seem to work well. I'm happy with the Futaba radios, just wish they had a dedicated 2.4 version (non modular) for the higher end models.