Here is also a couple of worthy consideration:

http://www.towerhobbies.com/products.../hrcj0253.html

http://www.towerhobbies.com/products...futk6000m.html

I personally prefer a 7 channel radio for use on Nitro/Glow powered helis as they are much more user friendly if ever you install a governor.

3 channels for cyclic, 1 channel for throttle, 1 channel for collective, 1 channel for gyro mode selection and the 7th channel for selecting different rotor speeds.