I believe that virtually all of the diaphragms out there for sale are the Asian sourced parts. I have installed quite a few in T-35s and I am very happy with the results.
in one way, reliability, they are far superior to the originals. The original leads were super thin, like a human hair. The replacements have thick leads that don't burn out when conducting power. When you pull the old ones, it is inevitably the lead which is toast, not the diaphragm.
Installing them is not that easy, but if you have DIY soldering experience it is quite doable. Let's be honest, the EV tweeters are peaky no matter what diaphragm is in them, which gives them their characteristic sound which I, for one, like. I know, I'm deaf.
