Do a quick and dirty offline edit with full clips, no cross fades, to pick the best footage and save it. Then start working on a copy of that. When you get past your offline then you can go back to your first pass offline and sync only what you need to sync. You will still have your
slates on your first pass copy. Then just import your synced footage over the top of post offline edit. It can save a lot of time that way.
Terry