I used a model similar to the VP112 for several years once I discovered it after using a bag suction device for a couple of years. If you are a cook it's like discovering demi-glaze for the first time. The ability to do liquids and process as many bags as you need to without having to wait periodically for the unit to cool means that you use it every day, instead of periodically for meat and other "dry food". The VP 112 did have some issues that got to be a pain after a while; two-handed lid lifting, slow vacuum creation, difficulty cleaning up after warm liquid boilovers, etc. But I liked the ability to use larger bag sizes then the next size machines in the lineup. So when I got a chance to purchase a refurbished VP 321 at a price that was less then the VP320, which was what I was saving my pennies for, I leapt at the chance. This thing is awesome, in a brutal sort of way, compared to the VP 112. First, it takes only 13 seconds to peg the vacuum gauge instead of 40 to 50 seconds I was used to. And the double sealing bar means that I frequently can operate it only a quarter as much. The ad in the website seems to insinuate that it will take as long to create a vacuum as the smaller units. But it is insanely fast. And the sealing of the bags is much, much better. But the equalization of the pressure is also five times faster and makes a rather loud woosh that scares hell out of my dogs. But believe me it's worth it.