howardporter - in 4.5 there is a way of working with a proxy model which I haven't explored yet BUT the simplest way of getting a mirror image to update is to check 'Instance' when you duplicate. That will do the trick - a glitch or two may cause it to stop updating in which case you can erase it and make another one. Works like a charm.

Nice model - I think it's going to be a good cartoon version of you.