Psvane Teflon capacitors real or fakes?

These are great looking capacitors and supposed to be competing against the Audience, Rel, V-Cap, and Sonicap Teflon capacitors. A couple of my tweaky friends who have no end to new capacitors gave them a try and had one quit after a month or so, and with the wire cut off, no return possible. So they cut it open, yes they are curious, and according to them, the guts looked like mylar, measured like mylar??? Could these not be Teflon caps after all??? I open this for discussion with some of the tweaky electonic minds out there to get to the bottom of this. If they are not genuine teflon, I would not want fellow audiophiles to get ripped by another false claim. But to be fair, real verifiable data should be submitted here, no guesswork. I trust my friends, but I did not do the test, so I open it to other philes. Hey, I like a great deal too, but if it is not as advertised, I get pissed too. Take a look fellow philes, and lets solve the mystery....Jallen
I wold like to point out that besides not having a Teflon dielectric, the Psvane cap foils are made of an alloy that is 99% pure at the most (two nines).
"Beryllium copper (BeCu), also known as copper beryllium, beryllium bronze and spring copper, is a copper alloy with 0.5—3% beryllium and sometimes with other alloying elements....Due to its (poor*) electrical conductivity, it is used in low-current contacts for batteries and electrical connectors."

* my comment

No wonder many users were disappointed with the sound quality:
Mylar is rated below Teflon, polypropilene and polyestirene in sound quality (and measured DF).
Berillium copper is a springy, impure copper alloy with much lower conductivity than copper. The symbol for beryllium copper is BeCu, not Cu

IMO the products were misrepresented and the buyers are entitled to a refund and/or damages, according to US law.
GF cannot absolve themselves from liability here as they are a direct extension (contractually I suspect) of the manufacturer.

Ignorance is no excuse.

Will be interesting to see if they step up.

Bottom line is if you lie down with dogs, you're going to get fleas.
The DOWNSIDE of pure copper is that it oxidizes like crazy and the resulting oxide is a diode.
Not at all how I want a capacitor to act.
What is the conductivity of BeCu? And to go all metalurigical on you, how much Beryllium is added to these alloys? I know their must be a bunch of alloys with who knows what else added.

Question: What is a good copper alloy which has low oxidation potential AND the requisite good conductivity?

Failing THAT, does anyone SEAL the cap in an inert enviroment so the copper can not oxidize?
Credibility is everything in the field of component parts. It's not realistic to expect the end user to dissect caps or other parts to confirm the materials claimed to be used. I was skeptical from day one about Psvane, Treasure and Grant Fidelity due to all this talk about sole distributor, counterfeit copies, testing and grading, etc. Now GF admits that the caps were falsely represented. Just speaking for one consumer, I will never buy anything associated with Psvane (or GF for that matter).
I will never buy anything associated with Psvane (or GF for that matter)-Salectric

Couldn't agree more!