To guest nick long, my 52SDR-9 has the same neat cross style fret markers. It is the only Sigma I have seen with it. Mine is a little earlier, has the Greek Sigma symbol on the headstock. These 52S models were a professional series and really well made, with great sound, even if they did have strange laminents on back and side. They were higher end than the DR-7. Enjoy your guitar.

To guest Karen. Yes the DM-1 is the lowest quality, but is still worth every penny you paid and then some. The case could be worth the $75.