Hi John, As a retired chef, who prepared and cooked with high end vacuum sealers, and restaurant quality Souvide machines. I feel there are better machines out there. I have included a link to one that solves a couple of inherent problems for the amateur cooks, cooling. It can be an expensive method of cooking and most grocery store proteins, aren't "clean enough" to successfully cook something at 130 degrees for 6+ hrs. A lot of people also don't like the rubbery appearance and texture of proteins cooked this way, so after cooking most restaurants will sear it to create a crust. Hopefully this will help you evaluate this type of cooking, and please feel free to PM me if you have any other questions.
Mark
https://www.cookmellow.com