I use a tuck shrinker setup for doing more rounded things ala fairings, tanks, if you're making something that's more or less flat but has some weird curves to it, the hf jaw shrinker/stretcher is more than fine, but it has it's use. the tuck shrinker lets you shrink the metal further into the part, so with a tucker, I can begin shrinking 2 or 3 inches into the part and really move things around, the jaw type really is only meant for a flange. also, my tuck shrinker is two steel tines ground to a rounded point, welded to a piece of square stock, which is welded to a round surplus drop of 3/4" steel, welded to another piece of bar that I can clamp in my vise. total cost was probably $5, many of my tools are home made, you don't need to spend all that much money for a lot of the metalworking tools you'll need.
