One-Shot Drain Cleaner

It does clean drains, at least to an extent.  It also cleans most other nearby surfaces. For 'cleans' I mean dissolves.  Its 91% sulfiric acid by weight, although I don't know what that works out to in laboratory terms.  Certainly follow the labels and use with caution, i.e. rubber gloves, not latex or nitrile, and something over your eyes as a minimum. It will discolour and later burn through clothing, skin, etc. As a shower cleaner, its fascinating.  That plus the baking soda I used to neutralise it (I wasn't the one who applied it, in case you wondered) made the shower whiter than it has ever been, at least since I've seen it. That said, I'm fairly certain it took some of the plastic with it. 

I can only imagine it has a similar impact on the drains, but I'm sure it does help dissolve organic matter. It didn't solve my problem, as it was too far along the pipes and they had to be taken apart outside.  It makes the drains frighteningly hot, and when the drains remain backing up it smells of sulphur. For ages... at least a day. You only need reasonable ventilation if it works, but have LOTS if it doesn't. This is the 'first' thing a lot of plumbers will try, so its worth a go (especially if you can't easily take your own pipes apart.)  They recommend regular use, so maybe it is mostly safe for your drains. I'm more ok with using it in rental properties, and there have been stories of it eating rubber casings on pipes.  Still, like any powerful chemical it can be used for good if you are careful!

Cost 1-10 with ten the most expensive: 4
Value for money 1-10 with ten being the best: 6
Durability 1-10 with ten being the most: 10
Usefulness 1-10 with ten being the most: 7
Importance 1-10 with 10 being the most: 6
Smile Factor 1-10 with ten being the most: 1
Cool Factor: 1-10 with ten being the most: 1 

*Do I think its the best in its field: NO
*Could I live without it: YES
*Target gender, age range, and possible further demographic targets : Adults, Homeowners, Renters.

Disclaimer: No financial interest in this company and no-one else asked me to do this review.