I am not trying to step on any toes here but please stop misleading the OP, Flight metal is not duct tape, it is simply flight metal covering. about .0015" thick with a supper adhesive applied to the foil.
I have both the 1/8 scale and the GS P-47. Both are glassed with .5oz cloth and epoxy resin. the 1/8th scale is painted the GS has flight metal. To the OP I want to say there might be a small weight gain with FM. but maybe only a few ounces. The scale look FM provides has no equal if a bare look is what your after.
Finishing epoxy resin will cure in about 2 hours, and can be easily sanded, any weave that is showing can be filled with spray can primer. I have used this system for over 20 years, makes a base for finishing the model.