Just an update, I checked the calibration on one of my pens today. I have several, both V1 and V2 models, and tested with a V1.
I loaded a spent cartridge with tap water, installed a used needle (nice not to have to worry about sterility), removed the air from the cart and primed it. I popped the top off of an empty 3ml vial and injected/squirted 10u, 40u, 50u dosages. I then sucked up each dosage of the water with a .5cc insulin syringe. All three measurements were spot on.
If anyone has a more accurate way to test pen dosage please offer upgrades on my process. I will probably test my other pens the next time they are empty.