I think the best thing to do would be to try a few materials out to see how you like it. Personally, I like allen wrenches. But, oh man, are they a pain to shape. I keep one allen wrench tensioner for my American locks because they need a lot of manipulation & some tend to need a bit more tension to open them.
I've tried brick strapping & it has worked out good. I've tried butter knives too, but that's a bit on the stiff side. I like stiffer feeling picks, but a lot of the ones that can be ordered are made of spring steel. I feel that the stiffer picks will give better feedback, IMHO.
But, the best way is to go out and try for yourself. I've actually found as much enjoyment designing new picks & trying new materials as I have with picking w/them.
-Rob
Sorry this doesn't give a definite answer to your question
