I like the drop test and recommend anything under 5 bounces for general play. As a second test, you should be able to throw the paint at the ground (solid wood or concrete) and have it break every time. If it bounces, then its too hard. You have to reassess if paint breaks on first drop. You don't want something that is so brittle that it gets crushed in your pods or by the force of your hopper.
I like paint that is super brittle. I trust that my level 10 setup will shoot anything and I want the paint to break if it even comes close to my target. If the paint will make it out of my barrel, then it passes the "too brittle" test.
Except for the Automag in front, its usually the man behind the equipment that counts.