FWIW, I did a full check of the my factory new M1B timing prior to first start (sounded like a good idea, and I was curious to see!). Both sides were dead nuts on 25 deg, per the data plate. I was happy to see this, and happy to be able to verify this myself with my buzz box. The biggest challenge was to identify the "dot" on the SkyTec starter housing .. it was there, but looked like an imperfection on the plating until I squinted the right way. Cross checked with the case split line and all is good now.
Interesting to hear, though, that the factory test was done with factory mags, and mine were slapped on after. I'd be TOTALLY HAPPY if they ran the shipping mags for a hour-ish before putting it in the crate.