I have two Vauen Churchwardens, though not with Meerschaum, but they are some of my favourites just because of the 9mm filter slot.
As far as the draft goes, out of the four brands of Churchwardens I've handled Savinelli is the only one that uses a significantly different stem from the rest. If you have a Nording Churchwarden or Cobwarden, Vauen is going to be roughly the same as those. It's a medium draw, not tight but not particularly free. I gave away my Savinelli before I started to pay attention to these things unfortunately.
The other thing to note is the bowl is on the small side on the Meerschaum lined pipes.
Vauen in general is very good with their engineering though, top marks for drilling and such.