Really sorry to post this kind of message.
In may 20011 i have ordered 2 einsteins 640, 1 cyber commander, 1 VML, 2 cyber command transceivers and a large octabox.
As i live in Moldova, i had to order my equipment with a help of a friend who lives in US. I have received my flash units as well as the rest of my equipment in august 2011.
First einstein stopped working in october 2011, just simply stopped flashing, the screen was on and the flash counter continued to count flashes but the lamp didn't pop. I have changed the lamps and fuse but nothing helped. Brought it to the local service where they repair different kind of flashes of different brands but they were enable to repair my flash unit.
I didn't wanted to resend my flash unit to Paul C Buff because it would take to much time, and it cost's a lot of $$$ to send something in US from Moldova. Plus local customs asked me to pay some extra fee about 120 $ which makes no sense.
My second flash unit started to have a strange behavior in Nov. 2012. It counts about 2000 pops (dont use it a lot). Now when i plug it in the VML the screen is blank and it's blinking. I was unable to shut it down as it didn't respond to any button.
I managed somehow to shut it down and it started working but the modeling lamp is blinking slowly... some times it's just dimming slowly and then comes back to normal.
Here is a video...
http://www.youtube.com/watch?v=qdH6P1uHIqAWatch it till the end to see the modeling lamp behavior.
Today it completely stopped working. The screen is blank. I can't shut down the flash unit pressing the button. Nothing works. Only unplugging it from the VML makes it shut down. But when plugging it back the screen is simply blank.
Now i don't have any flash unit that simply works.
The problem is that i have a some wedding photos to shoot in February and i really need at least one flash that works.