As one who flies planks, helis and now multis I can say that if you can competently fly a heli you'll have no trouble with a tricopter. It is somewhat different but awesome fun.
I'm still to get a good gopro vid with the tri (my fine tuning of the PIDs was interrupted by a rx failsafe - see vid 1).
Whereas the Bixler, about half the price and not a bad aircraft for gopro (see vid 2).
Vid 1: Tricopter crash
http://www.youtube.com/watch?v=TWcnxAV8Azs
Vid 2: Gopro on Bixler
http://www.youtube.com/watch?v=55YB6eLYmYk
I'm still persisting with the tricopter (when I have time to complete repairs) as it will be good for particular photo/ video styles (e.g. where hovering or slowing down will be important) whereas the bixler will be good for other styles (e.g. following another glider over a hill, which I plan to do one morning).
And youtube shows many excellent tricopter vids!
For the record my tri is much like the Windestal version except controlled by multiwii.
Go for it!