I think it will cost far too much to justify the extra 2cm clearance you get at both sides when the mirrors are folded. I have the foldy mirrors on my R32 and simply the MK5 Golf foldy mirrors are a joke. They dont even fold in full for a start let alone give you much more room either side. Unless you can do it for under 100 quid I would forget out it. My opinion of course.
^^^^ for got to add courtesy lights you get under mirrors are a nice little touch but not essential