You can fit with them with some bilstein dampers, I went the whole hog with the B12 kit as I didn't want any surprises, changed the top mounts for s3 ones too.
yours will have 50mm struts as apposed to 55mm like mine on the s-line,
I know what your saying about the sportline as they do work...
I went pro first and was so impressed I quickly went lower with the sportlines and they are perfect, car sits just right and not too low and the ride is impeccable without looking chavy and still retains an amount of oem look to the non purist.
Yep mine is attached to the vacuum pipe that goes to the inlet manifold. I had the same question as I bought mine 2nd hand too.
This may help you out. its the same place you can take a boost tap out for a gauge.