I love my food saver, and I have an ooooollld model that I got off craigslist for like $30. My food saver isn't built to do heavy sealing, but it is able to do it. I hear the motor struggle a bit though.
The biggest complaint I hear is people buy "off brands" bags and they don't work with the food saver. I have a box of knock off brand bags and I hate them. I can seal a package with an off brand bag, set it to the side and seal it with food saver bag and by the time I'm done with the food saver bag the knock off brand sprung a leak. Spend the money for food saver bags, it will save you much frustration in the long run.
Although, I can tell you about my secret....
www.thesweetattack.com
They have a "knock off brand" of food saver bags that ACTUALLY work. And they are a fraction of the cost.
As for what model you should buy, get a bigger one if you plan on vacuum packing whole birds, and bigger items. I think Cabelas sells the "game" foodsaver. I want that one, as it has a bigger motor. But, not saying a lesser priced one won't do the job. Get what you can afford, and i'm sure you'll be happy!
hope this helps!