I ordered a new head and exhaust for my '78 MGB and as I waited for them to arrive I decided I liked the look of the wrapped heads. After looking at all the alternatives, I chose this product mainly because of its relatively low cost; My MG isn't a hot rod, so power and temperature were secondary. I bought a 50ft roll because too much is better than too little and I wanted to install the exhaust as soon as possible. 50 minutes was too long but I don't regret it because I think 25 minutes wouldn't have been enough. I read the instructions (it's not rocket ops) and installed it with no problems. First, I simply "dry wrapped" each section, added about 10 inches, and cut it off. Soaking in water (as directed) made it malleable and easy to work with; It takes shape and stays in place when wet. With wetted material, when you wrap it tightly it tends to narrow only in width (but not in length). to cover the entire section and an extra 10 inches was definitely needed. To give you an idea I used 4 sections for the head totaling about 30 feet. The short sections were 5ft and the longest was about 15ft (this was the one I had to wrap a few times to cover the full length). I'm glad I bought it; Easy to install and I like the look.