I'm not calling it bad. But for me I have lost alot of faith in so called field installed membranes. In addition nobody has ever given me a difinitive answer to how to control the thickness of any sprayed in place systems other than "the intstaller has to have an eye for it." So you are eyeballing your work? Seems like some spots will be thicker than others.Beacause it is a 100% seamless roofing membrane system with more elasticity than all of the aforementioned systems, except maybe EPDM.
Because I install the entire roof myself. Because it is both flexible and tough. Easily repaired if some type of mechanical damage does occur. Because it withstands ponding water indefinitely. Because it has excellent resistance to petro chemicals and animal fats.
Becasue it holds up as well or better than the other previously mentioned systems.
It is not a foam, but a two part instant set membrane system.
The only thing we cannot go over is tar and gravel. For this you need to install a layer of foam first.