I like everything about the JR3550, but its not digital and that can lead to issues when running a Helios.
For those that nee dto know what issues those are-if youve got another car on a digital servo and the radio is in HSR mode and 2-channell-you should have the 12th scale on 3ch Normal mode-requiring flipping the switch bwteen runs. NO thanks.
I am switching back to the KO diigital mainly for that reason.
I have run my Helios with the JR3550 in 2ch, HSR mode-without a hitch-but at one track my car went nuts. Never again.