One other thing to consider, is to take a really good look at the blade clamp. Many of the clamps on the value priced saws are made of a small piece of machined metal with a 2 to 4 mm cut taken out of the center. The right side will usually have been drilled and tapped to accomodate the screw for tightening. It's not a bad design, but if blade change requires a wrench of some sort, it's extremely easy to over tighten it. What ends up happening is that a small crack forms at the back of the blade clamp. Every time you tighten the screw, the crack prevents the clamp from holding the blade securely. I had this happen on my first scrollsaw. It all depends on how much material they left after machining the center portion where the blade goes.
Barry