ok im really not one to get aggro but ptfe will not brake your marker or void your warrenty, its great for quick fixes or fitting's that are going to be removed frequently.
This hole ptfe myth came from the timmy forum on pbnation and was created by stupid americans
ptfe is soft, if it were to get into your solonoid a wipe clean would fix it.
wet loctite on the other hand could possibly get in somewere tight and glue it togther
i use both products and have never had a problem
ive looked at quite a few manuals to check this and none of them say not to use it, and at the same time none of them recommend using loctight .
The only thing that most manuals say that will void your warrenty is using the wrong oil or grease
ill save you the trouble and post up a few manuals so you can search them to try and prove me wrong
timmy
ion
race frame
edit: infact in the timmy manual it recommends using tpfe tape for some situations.