As a latecomer to the multicrew system, I was worried about fitting in so to speak. I can safely say that so far, 2 years later, I haven't flown with a captain I couldn't get along with. Of course, I am a bit older than the usual F/O I guess....... Seems to be at my company there is acceptance of each others positions, there is encouragement and help given, and an expectation that as F/O, when it is my sector, that I will make the appropriate decisions as required. Always of course subject to the overall agreement of the PIC. One of the captains I fly with has a saying to put the overall responsibility issue into perspective, he sums it up with - "Your cock-up, my arse!" I've never forgotten that!