Vaporific
All who wander are not lost...
I'm sure PBW works however it's extra steps for me and I'm not too comfortable with the fact it has stripped finishing off some devices. ISO suits me just fine and doesn't require heating. Perhaps my threads don't quite match yours but they're good enough. Except...Yeah I will never PBW my HT PFE, but I also hardly use it to preserve it lol, glass alone scratches it, I use it native or with a Teflon adapter.
I wouldn't really recommend a coloured PFE at all, they scuff up in a matter of days if you're not so careful.
The last few times I've cleaned the PFEs I've just spent a few mins with isopropyl and a pipe cleaner.
But today I'm going to give them a proper wash. With plain metal it's no drama, super easy and faster than any other method I can think of to fully clean (without increasing risk factors, PBW is safe stuff and free rinsing).
Good luck with purgatory! It's a gruelling process
Now to read the HL instructions to send in my Ti to RMA Purgatory. And I just watched the movie Inferno (written by Dan Brown) too but the book was way better. Yeah, Dante knew a lot about Purgatory and Hell...