Pros: cold water saves energy, works as well as normal detergent
Cons: hard to find, a pit pricey
I first bought a box of Tide Coldwater at Target and was very happy with it. It saves a ton of energy by not requiring hot water (up to 80% of energy use per load), and it works just as well as any other detergent. It does cost a bit more. Target stopped carrying it and I couldn't find Coldwater in any store, so I had to buy it from Amazon, and had to buy 3 boxes of it. So it ended up costing $17 per box for 63-load boxes (146 oz).
So I've got enough Tide Coldwater to last me for ages, but that's fine, because I like the stuff. Can't complain about effective laundry soap that saves 80% on energy.
One thing to watch out for is to make sure you use the cold water cycle. My sister-in-law once used it in the regular warm water cycle, not knowing it was coldwater detergent, and ended up with soap residue on all her clothes.
For those claiming this product deserves 0 stars because it's not 100% green, I think that shows a degree of snobbery, to be blunt. Many laundry detergents don't work well in cold water. Saving 80% of the energy per laundry cycle is extremely green. Could it be greener by being biodegradable and without petrochemicals? Sure. But does that mean it's not green at all? Absolutely not. Especially since a lot of people trust Tide and don't know about greener detergents. Would you prefer they continue using warm water to wash their clothes, or at least switch to cold water?