Comments: I had a hard time choosing between this and 20mm/AA version. I used the computer at hobby shop to try to investigate whether this version was used summer of 1943 but could not get any useful info. I ended choosing this version over the 20mmAA because of the higher caliber, however I found later that this 37m/mAA did not appear till late 43'. So if I get a chance I'll pick up the 20mmAA version. However this might be the next model on the work bench, so I can work out any kinks in building so other Sd.Kfz's come out better.
History: Wikipedia on Sd.Kfz. : LINK,