Plastic tubs are fine IMO.Not dissing the idea of sous vide, I'm talking about his setup.
I've got a DIY ghetto sous vide at home. It's a six pack beer cooler with a small hole drilled in the lid for a thermometer. I adjust the water temp by adding hot or cold water from the kitchen sink (or adding boiled water from my kettle) every 20 minutes. It's not as exact as a Joule or Anova but it's pretty damn close for something I spent $10 on.