I reached out to the company also and received clarification on the Mono 3D product. As I feared, it is not 2 Mono S heads, it’s just one head with enhanced swiveling capability.
Curious, what were you fearing? To me, and they clarified the same point to me, 90 degrees both ways makes it even more versatile. Also, the 3D comes with 2 heads, with second head only running an additional 170 euro; it almost seems like a no brainer. I can't think of a reason NOT to just go that route if you want two heads.
The price is close with what Festool was charging for two heads, vacuum pump, and foot pedal. I sent this to the rep, my buddy wants a 3D setup too, but no pump. I have an older pump, and the rep confirmed the 110v pump will just ship later, which is fine.
Setup with two heads, pump and foot valve comes to 1415 Euro/$1618 US, of course before shipping, which was in the range of 90 US bucks. One thing i still have not got pricing on yet is the additional round and oval plate sizes; there are 3 other round sizes and 4 other oval sizes.
So yeah, it's fair to say, it's a few hundred more bucks. It is the most affordable/quality solution compared to the Vac sys i've found though. It's not a "cheap" option by any means, but if you were in the vac sys ballpark, this can at least get you a still made/supported option.
Also, FYI, i got in touch with a US supplier; they tacked on 1200 US dollars for the pleasure of getting it shipped here for me; I passed.