Bobby -
Those Jiffy Pop things don't hold a fire to the
Whirley Pop machine. Jiffy Pops are inconsistent, at least in my experience (and maybe I just never got the technique down), and it was hard not to get them to burn. And when you're successful in producing a tasteful product, there's usually a TON of unpopped kernels. The Whirley Pop is simple, easy, and has perfect results every time, with nice fluffy popcorn. Then season to taste.
I'm guessing the "crud" in the muffin man machine is probably minerals - that's what you get when you distill water. Spring or filtered water may help, and will certainly be better than well water, but if you want ZERO crud, buy a $1.50 gallon of
distilled water at the grocery store. It has virtually no mineral content, and should boil dry while leaving no residue.
Dave