The Simpson/BSW Mod. W625's came in several different models, with the Mod. W625B being the most common. Although they are earlier than the DSM's & KKW's they don't seem to be as sought after by collectors.
I honestly think this has to do with lack of knowledge on the part of collectors.
Bob Simpson of Galesburg, Illinois is in the process of writing a book on German Training Rifles that is supposed to be done next year. Watch these go up in value when it comes out!
Personally, I haven't seen many with the SA Gruppe Hochland stock stamping. The most common seems to SA Gruppe Kurpfalz. The stock plaque definately adds value to the gun - how much sort of depends on the buyer, I guess.
Most German trainers seem to be in fairly good condition. I hope it's just the pictures, but yours looks to be in slightly less than good condition. I can understand enough German to get a general idea of what the plaque says, but will wait for someone better than I. Basically about Best Performance in the Sturm 16/J2 for Shooting Competition for the HESS-Cup/Goblet, 1937.
Hope this helps....

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