Yes, rosters at Netjets are rock-solid. If you do not agree to extend or show a day early (for extra-$$$) then you just don't that and they will look for someone else on the fleet. In this sense we are the "airline amongst business jet operators". I personally would not go for another business jet operator outside Netjets, I'd swallow the bitter pill of going back to the airlines, if I had to leave. Exception: find a great private owner who genuinely takes care of his crew: then you get good money and you make your own roster, you pick your own hotels etc.. There are not too many around and you mainly get those jobs through connections.
At the moment I would NOT change company, the next economic downturn is around the corner and quite a few operators/airliners will not survive it.