These days ProRes runs very nicely on Macs - I have been using it for years on all my shows. 4:2:2 versus 4:2:0 - no contest for me.

ProRes uses hyper threading which means it performs very nicely on modern Mac Pros. Don't bother with HQ. Nice for Post Production. Not much use for Catalyst as none of our displays/ projectors/ LED walls can render 10 bit.

With respect to Audio synchronisation - it is worth bearing in mind that Catalyst prioritises audio playback over video, and this can create problems when synchronising across multiple machines/ layers. Try and sync your video layers to the audio/ video layer, as others have suggested. Also bear in mind that the performance takes a bit of a nose dive when you use audio playback through Catalyst.

Hugh