The product worked good for us. Our house is a very old family house with a septic tank. We replaced the tank and drain field about a year ago but haven't gotten to replacing the drain lines in the crawlspace. So needless to say, years of build up and adding new build up has led to slow drains and the occasional hairball clogged shower drain. I added the product to the shower and tub drains and to the sink drains and to my surprise after they were flushed out, the drainage was great.
WARNING. This stuff stinks horribly! It smells of sulfuric acid/rotten eggs. But it works, and the smell goes away.
Bottom Line: Yes, I would recommend this to a friend