It reminds me of the Twins Freestyle Cool but with a conjoined seat rather than independent ones (worth bearing in mind because although you would maybe like your twins to be best of friends, if they do fight, then they are very close in a conjoined seat!)
My initial reaction simply at looking at the photos and spec is that its wider than a standard doorway. This is the first rule for me with doubles. If it doesn't fit through a 76.6cms old standard doorway then don't buy it. There's nothing worse than needing to pop into the bank or doctors, but the pushchair has to stay outside, and then you have to carry two 10 month wriggling bundles weighing 9kgs each (just at a guess) whilst paying with your arms hanging off, and then you have to manage getting them both back in safely and doing two harnesses up - one with just one hand whilst holding the other baby.
The fold size is huge. I have folded similar pushchairs, and even when the chassis goes flatter than that one, they are still large. Plus you have a large bulky all in one carrycot and seat unit on top. If you have a car, you will need a massive boot for all that lot. At least separate seats may well stack?
I bet this is lovely to walk with though with the air tyres. If you can get this through your front door, and you only walk, then buy it. If you want it to go in your car, then make sure it will fit, and start thinking if there are any doors eg doctors, pharmacy etc where you wont be able to go if you choose this beast :)
Lovely big basket and adjustable handlebar though.