A few years ago a couple guys did a test on sound deadener. well after testing they developed a far superior product and marketed it. eventually everyone followed but IMO they still have the best stuff.
not only that but they also realized that with the high quality stuff not NEARLY as much had to be used. 1 1/2 sq foot is more than enough for each door. 4 CDL tiles per door is overkill.
sound deadener isn't for reinforcement its to stop ringing and resonance.