i use dynamat extreme, only because i got a good deal on it. but most deadeners are the same, as long as the have the same thickness. edead, from what ive heard has a tendency to fall off....not too sure about the foam spray though.
most people ive heard use the spray say they love it and it works better than all the dyna and edead stuff...could be personal exp...i havent tried either yet...foam supposedly a lot easier faster than all the other stuff 2
I've had a lot of experience with sound deadener. Dynamat xtreme is the best (easiest to apply, best deadening, and sticks well upside down)...however its the most expensive...look on ebay for a bulk pack for around $125...The spray doesn't work as good as dynamat xtreme, but is good for cracks and hard to reach places and it is usually black so you won't notice it. Other deadeners, are cheap and work, but not as effectively. The installation process also takes more time and effort. Depending on the temperature, you may need a heat gun and it may not stick upside down for long periods of time(rear deck, trunk lid, roof)...personally I've gotten the most results from dynamat xtreme.