Jack,
Don't worry too much, I have been using a Black & Decker 12" hobby bandsaw for the last 25 years or so, and a bit of work fitting roller blade guides has turned it into an amazing little machine.
If you are going to be using it for cutting any type of metal, you need to get one, if possible, with variable speed or even a two speed one should cope. Metal cutting likes to go a bit slower than wood cutting.
Mine was designed to take either a 1/4" or 3/8" blade, but with top and bottom roller guides, it has run 1/2" blades for most of it's life.
Good quality bimetal blades are the ones to go for, I get mine made up specially because it uses such a short blade, but it now cuts all metals, including stainless, with ease, and if I am still around, it should give another 25 years of service.
John