ORIGINAL: gaRCfield
Also the extra channel means you have more capability of mixing things together; you can independently trim dual flap servos, dual aileron servos, dual elevator servos etc.
Yup and no matchboxes, servo reversers, etc.
ORIGINAL: gaRCfield
It would be a while before you needed more than 6 channels though, most likely not for first, second, third, or even fourth plane.
Hah, I needed six channels on my third plane...
Buy something like a Giant UCD 3D and seven is not nearly enough channels!