I wouldn't hesistate to buy one from amazon if it had good reviews I guess. They aren't a complicated machine, a small pump, seal and a heating element, so I think it would be fairly hard to get a horrible one with a little research on the specific model.
As long as it fits an 11" wide bag , the only drawbacks would be if it couldn't fit a LARGE roll in its storage area, but, not a dealbreaker I guess. The standard "foodsaver" brand machines fit the bags I list below, they are pretty big rolls.
Bags are where the cost comes in- I can't stand paying crazy prices for the bags. I finally found these and have bought the several times now -
https://www.amazon.com/dp/B07Q1F2VKC/
They seem exactly the same as the foodsaver brand bags, only nowhere near as expensive.