Jan Allaerts Cartridge Experience?

I've heard some good things about the Jan Allerts MC1B and MC1B Mk II cartridges . These seem pretty rare and there seems to be limited fedback on them.

Do any of you have direct experience? If so how do they compare to other top cartridges, e.g., Zyx, Lyra, Dynavector, Koetsu, Clearaudio?

Thanks for the feedback.