Yes, try a frost resistant product. Rain-x Ice and Rain X-frost should be able to do the job well. Just apply the product on the dry mirror surface and wipe. Water will bead and frost and Ice will not form. Its that easy.

I use this approach on the windows and as a result I rarely use the wipers even under heavy rain or snow.

Look, us canadians get the heated mirrors but our US friends get the remote trunk release on the fob plus the Navi option. Either way we look at it, we're both left wanting.

Cheers;

MSantos