Too bad about the consumption, but 1/3 qt in 2k mi isn't bad. Or should we be saying 1/3 liter? Hopefully it stops by your next OCI.
The fact that M1 ESP comes in liters is both good and bad. It's nice to use an even number of bottles to fill the engine to midpoint on the dipstick (4.0 L), but you don't get to top it to the "full" mark like you do with 4.5 quarts.
Good to hear ESP performed well on a really cold day. Care to compare it to PU or Castrol OE? I haven't driven my car on M1 ESP yet, but I will in sub zero temps this week. Of the oils I've used on brutally cold days Redline 0w30 is clearly the best, followed by GC and then closely by Redline 5w30. In -10*F or below the engine is pretty sluggish and cranky on RT6.