Take a look at AC43.13, specifically at the workmanship standards around wires. In reading this wonderful tome we'll find the acceptable amount of nicked or damaged strands for our most common wire size, 22ga, is... ZERO.
There are several strippers referenced here, particularly the ones immediately above, which will not strip Tefzel wire without nicking a strand or peeling a sliver off a strand or removing a complete strand. Definitely NOT acceptable for aircraft use.
Yes, I know, I'm Debbie Downer... Sometimes we have to pay a little extra to get aircraft quality. Hmmm... maybe that's why not many of us fly behind a Briggs & Stratton or Tecumseh engine! :-)