Can't help with the size query Im afraid but I do like the look of the KU36s.
As far as I know you'll be the first to try them on a VX on the forum 
I've them also
but in 215/45/17 front
245/40/17 rear
How do you find them? What previous tyres can you compare them too? I'm currently on khumo ku39's but I fancy going for 215 45 16. I presume you don't get any rubbing?
Well, i've only done a few hundreds kilometers and on the road only so i cannot compare the grip.
They are installed on 8 x 17 OZ ultraleggera wheels ET 35 at the rear and ET 20 (15 mm spacer) at the front.
At the rear i've not increased the mass at 19.3 kg per wheel , the tyre itself is 11 kg . This is slightly lighter than a Superleggera and R888 225/45/17 combo.
No rubbing at the rear
At the front the tyre is 9.2 kg and when installed on its wheel the weight is 17.6 kg. It's 2kg more than with my 16" wheel but it's the price to pay to be road legal (in France)
The tyre rub on the clam at full lock at the classical location with this tyre size . However, i may not need extenders as 1 or 2 mm of clam wear could be sufficient.
So far the feeling is OK . They are quiet despite the thread pattern.
I still have to lower the car a bit more notably at the front and a new geo setting is necessary to really investigate their capabilities.