The OEM ones have a retaining rubber ring and sit flush.
These do also but painted. They fit from behind as OEM protude about 1mm.
Just bought some DOTZ alloys (told they were once yours?) Will they not fit MK6 without spacers. Guy gave link that states ET45?
Yes ET45.
Once SteveP's, then mine, then flc1962's and now yours. Right little tarts! 
That's odd, how come you didn't fit them. Way way nicer than everyday Monza's
(1) They ARE NOT nicer than the Monza Shadows IMO as theDotz look like 'any other wheel'.
(2) My Insurance Company at that time was going to charge me extra for non OEM VW wheels.
(3) I had a storage problem.
(4) Was quite unwell at that time and could not be bothered dealing and arguing with the then Insurance Company.