I had one years ago when they first came out. They're great unless you need to reseal the bag numerous times then the bag continues to get smaller. What I do and it's probably not the great but works for me. I take a plastic straw, close the freezer bag all but about an inch at one end, put the straw in down deep and suck out the air. Close the bag up quickly. Has been working for me for a couple of years now as I freeze my green beans and berries plus whatever sale from the grocery store after cutting it down to fit my needs. I also read as I was interested in Sous Vide recipes how I could seal a bag and get all the air out. They said to lower the bag into water slowly and the air would be pushed out of the top as you lowered it. Then close the bag without getting any water into it. Sounds like a good idea to try for me at least.