Toughroof has to be the BEST option for flat and low-slope roofs.
I was originally sold a bill of goods by Custom Metal Roofing (metal roof for 0.5/12 slope roof), and it was 8 months of nightmare, still not over, 2 years later.
After doing my homework (thoroughly this time), considering all the hi-tec systems, I decided I wanted more than a "thin fabric" on my house.
Tughroof was a natural choice. They removed the junky tin rooof, and installed the new roof in a matter of a few days. 3/4" of rubber-bitumen, with a polymeric ("suntan lotion") topping. They also did all the parapets, everything.
Had 1 small issue with some of the polymeric layer lifting and they were back in a flash before this winter to fix it (no leaks, I just want to make sure I'm good for the long-term).
The staff are all excellent, friendly, responsive, they take care.
If you are thinking about Toughroof, I would be pleased to share my experiences and show you my roof. Go for it.