I read about a possible ship date of 05/18. Vortex won't charge my card until it ships and I pre-ordered the first week they were announced. I'll update when I notice the card is charged or it shows up.
I am not too worried about thermal drift as I'm not in combat and don't expect to be in temperatures under -40* or over 122* F for very long at all. Even if I were, what are the chances the other guy isn't being affected as well? At those temps, you're likely not going to be Sgt. York at distance any way.
The sights are made of metal and will be subject to expansion based on ambient temperatures and length of exposure.
I cannot see any scenario where you'd go from one to another extreme in the same incident. Maybe running from the outside in the Middle East into a freezer? Even then, the temps wouldn't be -40 in the freezer. The distances wouldn't be so great as to detrimentally affect accuracy you couldn't hit your target.
If you ran from the inside to the outside (and were inside the freezer long enough for the metal to actually get cold and contract) there might be some issues but I wouldn't worry about it. Navy SEALs and other units have been killing bad guys for a couple of decades with EOTECHs.
Other manufacturers have thermal drift as well:
http://soldiersystems.net/2016/03/08...thermal-drift/
(this was obviously in response to EOTECH issues)
They just didn't hide it from the government and quietly try to fix or minimize the issue.