I have the same exact question as OP. Does the 3x Deluxe work with a 512 and MBUS? I've seen pictures on PrimaryArms website that have MBUS, but not with the Deluxe model. Does the Deluxe model clear the MBUS when its on the flip mount?
Also, whats the ETA on the 3x Deluxe Magnifier coming back in stock?