Surely the only catch in this is the owner has total say in the ac.
So if it has a dodgy VOR but he never uses it it is unlikely to be fixed.
Likewise if he wants to move it elsewhere he can without asking anyone.
BUT the aircraft is not being used enough, that is why they look for other pilots to offset the fixed costs and doing something unpopular like moving it will lose the revenue stream.
The other side is if any bills etc come in (and they do) it is down to the owner.
I agree with Slipslide about benign dictatorship and since the share is no capital involved you are free to exercise your vote with your feet at any time. Try that with a capital share group that does not get on.
I think they are a great deal, long may they last.