Nobody outside of a select few YouTubers with access to a demo unit knows that yet and even then it depends on how much you value their opinion.
It’s going to be a different flavour profile for sure as the burr size is different - 64mm on the Philos vs 83mm on the Duo.
Build quality will be better. And before anyone gets annoyed with me for saying that, the Duo is very well built, but it’s plastic, and the Mazzer is all metal. Mazzer are also probably the highest regarded grinder manufacturer for their build quality. In the home, it’s a non-issue really.
Something I’ve realised having played with various flat burr sizes is that bigger doesn’t automatically equal ‘better’ to everyone. I actually prefer the output of 64mm burrs over 83, it suits my taste better. I like the 54mm burrs in my x54 even more than some 64s.
You might have to wait until someone on here buys one to get a decent comparison to the Duo but the Duo is a great grinder so it might just come down to your preference. The Duo is also significantly less expensive.
Beyond that, price and actual release date is still unknown as far as I can tell.