There is no "new" production, as I think Olympos stopped making stuff around 2006(?) It is claimed that it is all new old stock, some (much) dating back to the 80's. I have a mid-80's vintage MP-200B, and have recently purchased several other brushes from Olympos Japan. For me, the older one is nicer, and works smoother. I notice there is a difference in the shape of the nozzle between the older one, and the ones I just received. I also ordered quite a few needles, as they are ridiculously delicate. It is not a matter of IF you will bend it, but WHEN. I bent one in the first five minutes of use by dragging it on the surface of the paper while testing how fine a line I could pull.
The brushes do work quite well, and the prices have them looking VERY attractive. I will say though, I am completely turned off by the lack of support Toshiya offers for the product he is selling. NO warranty at all. If you need a replacement part, as long as it is listed on their site, you are good - but if you need to ask, all you will get is that it is "...Trade secret", "sorry, hope you understand...". Shoot, he even told me if I needed replacement parts, just buy another brush to take them off of. It also seems to me that anyone that has tried to develop business around selling the brushes has gotten burned or turned off... Just an observation, on my part.