I have never flown in IMC with my autotpilot on. I don't trust it because of the wacky things it's done VFR so I just don't use it at all now. I had it INOPd for my instrument ride (per recommendation of the examiner so I didn't have to use it) and have left it that way. Maybe if I had something fancier than a Nav-o-matic I would feel differently, but that's how I learned. I think that an autopilot is helpful in IMC, but a requirement? No. If you can't hand-fly you shouldn't be flying in IMC at all. If you get an airplane with one use it by all means, but don't let your hand-flying skills deteriorate because you don't kow when you may need them.