Well on the upside... I decided last night to try drilling the holes larger in the 3 sockets that wouldn't fit on my Hansen trays. The 3/16" and 6mm were easy, there was actually just a little bit of 'flash' at the drive end of the hole, had each done in about 30 seconds. The hole in the 9/16" was a little undersized the whole way, by a little I'm talking maybe 1/32". Holy hell that chromoly is hard, it took a few minutes to get that one.
Playing with the calipers, I like what I see. The 8mm had the most difference out of what I measured, right around 1mm. The 5.5mm, 7mm and 11mm were fatter by 0.2-0.3mm. The 12mm and 13mm are both about 0.5-0.6mm more... and the 10mm is actually a little skinnier than my USA Craftsman! I was expecting a much bigger difference than what I measured.