Thanks, everybody, for the input.
Brompton is of course a very interesting alternative. I did testride one, a few years ago, then 5 minutes later made a ride on a Birdy, and was impressed more by the Birdy. But as stated before: the Birdy is just too expensive, and the 18inch wheels, I don't like them.
Brommies don't look as sleek and sporty as a BF or Birdy, but on the quality aspect they do score high.
Gonna check out the Brommies once more...