All I can say is that it works great. I haven't had any issues with and the clothes, towels, sheets and blankets all have come out clean. Really it will take a bit longer to know how good of a job it's really doing, but so far things are looking good.
The recipe I used is here, but I will give it to you too.
makes 10 gallons
1 cup washing soda
1/2 cup borax
1 bar of soap
1 5 gallon bucket
Grate soap on box grater and melt over medium heat in 4 cups of water, In a 5 gallon bucket fill half way with hot tap water, then add in washing soda and borax. Add in the bar soap when melted, give it a good stir then fill the remaining way with hot water. Let sit overnight to gel. This is your concentrate. You will need another container to dilute it by half. Use 5 ounces of the diluted mix. Make sure you give it a good shake before using because it can/will gel again.
Good luck and enjoy!