not your fault, but garmin perverted the use of 'calibrate'. you are simply checking the zero offset of the meter (which is one thing you should do before a ride), but it has no bearing on calibration.

a reading of 1451 on a quarq is definitely suspect, but as long as it does not fluctuate much that is better than high and rising (or dropping).

an analogy for zero offset is this: remember analogue scales? let's say you actually weigh 165 pounds. you step on a scale and it reads 170. you step off and it reads 5# with no one on it. ZO is the power meter equivalent of checking what the scale reads when no weight is applied.

calibration has to do with taking a reading at zero then taking a known mass (a large mass that is known to a high degree of precision) and measuring the unit's response to it. this defines a line from which you can extrapolate how the meter responds when any force is applied. power then comes from the force and cadence.

EDIT TO ADD: just because one zeroes their meter at the start of a ride and therefore it reads 0W when the only weight is that of a pedal has no bearing as to whether a meter is accurate when another force is applied. that's what true calibration is for.

anyway...your 2nd meter could be suspect. it raises a yellow flag for me.

cervelo? rotor makes a nice BB which allows you to run a 24mm crank on a BBright frame w/o any adapter. i put shimano SRMs on them. it's a special BB and a little hard to find -- the part #s are confusing.

also installed a rotor SRM on a friend's foil. it was their BB for bb89 & bb92 frames, if i remember correctly.

reach out if i can help you investigate SRM options. you might be surprised.