O.K. Here's the test-Future spraying on part of an M10. As you can see in the first and second pic, the Future appeared to have a "tooth". This leveled out a great deal with time, but it still appears more satin than glossy. I'm thinking this is good because the glossy finish repelled my first wash attempt. I sprayed the Future with a wide-flow nozzle on my Aztek airbrush with 28lbs. of pressure, from about 12 inches. I made about 6 passes; 3 horizontally and 3 vertically. Obviously, I masked half of the part in order to test some other weathering techniques. The good news is that my pin wash worked great.
In the third pic you can see the difference between a pin wash on a flat finish and a finish sealed with Future. On the left, you can see how a flat finish "blossoms" while, on the right, the wash on the Future pretty much stays put. The wash was Winsor & Newton Artists Oils Burnt Umber thinned greatly with Winsor & Newton Sansodor Turpenoid.
Hope this helps others who have the same problem with Future!