I have had two food savers. One was the lowest level one they made. It had to have been at least 15 or so years ago when I got that one after a load the boat tuna fishing trip in Port A. I vacuumed more dear, pigs, and fish than I care to count with it. Only reason I chunked it was the rubber seals went bad. I could have bought new seals but chose to upgrade models instead.
I used it for around ten years with no problems.
Next Food Saver I bought was the one that could do the hard plastic containers they sell. Again I vacuumed bagged more dear, pigs, and fish than I can count. NO problems with it at all.
About two years ago I was given a fancier upright space saver type Food Saver with a few more bells and whistles. Been using it regularly with no issues. I really like the marinating containers, I use them for to marinate jerky in half the normal time.
The only problem/issue I have found is around the bags, and I bet all of them have this issue.
I say that because the problem is not the machine it is the bags.
Do not use the cheaper off brand bags. I have used several brands of bags including Rival, Kroger, Wal-Mart, and the Food Saver brand.
I could not get the cheap bag material to vacuum very well at all and when they did the seal was unreliable. The cheap ones are just to thin and don't seal well. They also will get a hole from bones really easy.
Once I started using the better quality bag Food Saver brand bag material those issues went away. Last weekend I butchered and vacuum bagged three deer. The Food Saver never missed a beat. All bags vacuumed all the way down and sealed perfectly.
I also make my own sausage and vacuum all of that every year. I have never had any freezer burn or freshness issues when using the Food Saver and good quality bag material.