I tried it on a flying boat once before monokote covering....never again, what a mess! As ml3456 pointed out, it bubbled showed thru the film. I still use it, say around the perimeter of firewalls where I'm going to wrap the monokote around onto the epoxy resin sealed firewall, as it sticks it down to the epoxy coated surface far better than without.
And Chris300s - The thick Balsarite is all I buy, and I just thin it down to the desired consistency with Nitrate dope thinner. Trust me, it works great. A buddy turned me onto it years ago when we used to use thinned Balsarite on small tissue covered airplanes instead of dope because the balsarite stays a little more pliable and doesn't over shrink the tissue like dope does.

Cheers, Nigel