Rob,
Definately if there is any kinda breeze, Planetary high power imaging will be difficult but still do-able.
As fred says even a G11 at about 4-5K will only just cut the mustard at high power, your next port of call is a Titan, or new Celestron CGEpro.
You have a great mount just get out there and put a good 10" reflector on it and start imaging!!!
For viewing it'll be fine Rob, seriously that 12" of mine weighs a tonne and i do Planetary viewing at high mag now worries at all. You just need a Autofocuser so your not touching the mount or scope and it will sit still just fine.
JUST DO IT
Shane