Plastic Carboy Using A 5 Gallon Plastic Water Bottle As Beer Fermentor?

Using a 5 gallon plastic water bottle as beer fermentor? - plastic carboy

I currently use 6 gallons buckets for fermenting beer. I thought the idea of a bottle 5 + gallon of water as a glass carafe. Many vendors sell beer in plastic bottles, but I'm not sure what the resin identification code must be searched. My dice have a 2 and a bottle I have is a 1.
Anyone out there use the bottles?