Can both be used on one model. Future coat followed by sealer?, or this a deadle concoction?

I'm not sure exactly what you are asking. is the Model Master Sealer you are talking about the Metalizer sealer? if so then you should use it to seal the metalizer paints before doing anything else to the model.

or If By the Sealer you mean the gloss coat and or the Flat coats then yes you can spray them over the Future after it is dry. After painting the model is often sprayed or brushed with Future then the Decals are added.. If it is a military model and requires a flat tone then it is sprayed with a Flat Coat. or if gloss coat is needed you use that instead.

I meant Model Master Metalizer Sealer,