I would not know the number. They are sold in France, the Netherlands, direct, and in a few other places by distributors. My guess would be around 10 to 20.. it's probably not such a big upgrade compared to S7. But piano is as mentioned exceptional with it. Vocals as well. And the match to my headphone setup is more enjoyable too. But still, the m7 was great. Now, after 3 months, i am finished adjusting my setup. I can say safely it it a significant upgrade to the M7. It is not huge but it is significant. More definition and smoothness sums up the difference.