The biggest issue with the FA is the lack of direct drawbar control, you can do it with the jog wheel, bar by bar, but not ideal for playing live in my opinion.
I think they sound pretty good on the FA, but, they're not show stompingly good.. with some additional FX they can be. I've put mine through an old rotary cabinet in the past and it sounded really lively, on it's own however, the rotary emulation is good.. but it's not REALLY good, likewise the organs lack oomph in the lower notes... This can be brought back a bit with the onboard EQ and compressor, but something is lacking when you do that, and it doesn't feel 'airy' enough for my liking.
It's so hard to really give an opinion, because, in my experience, once in a mix.. be that studio or live, the FA really does sound rather good.... On it's own, particularly with the organs/rotary mix you can be a bit over-critical with it.
Have you seen this video? May help you:-
https://www.youtube.com/watch?v=iWno_8kJw4k
That's interesting as 'woody' creates a studio set and combines two tonewheel patches to give him decent upper and lower sounds.