Upper atmosphere is completely different, and surface is completely different. If it was even remotely similar I would give more stock to the latest 0z Euro. Today's 12z will probably be horrendous compared to the 0z, but even if it's closer than yesterdays 12z run is to the latest 0z, I'll consider it a win. (top pic is yesterdays 12z, bottom is this mornings 0z)
Edit: Reason I bring this particular part up, is were roughly 9 days away or so, although surface features are expected to be different, upper air features should start to somewhat sync up, which hasn't happened yet on the Euro.