Stainless Steel is a bad choice overall, it can't be soldered, its heat chacteristics suck, and the individual coils will short out if they touch. Nichrome is by far the best choice. First of all, it can be soldered. Secondly it's designed to handle constant temps over 2000 degrees F. Lastly, nichrome has a great side effect once current is ran through it and it heats up. Chromium Oxide forms on the surface of the wire and insulates the coils from each other. Chromium Oxide is black and has a powder look to it. This, I believe, is the "black soot" everyone complains about not being able to "clean" off of their attys. Flat Nichrome rings or spirals could very well be an alternative to coils.....food for thought.
