Hi, Highrise...I work here in Holland and for the most part wooden frames are the norm and UPVC are on new estate type housing projects (no offence to anyone)....I get the feeling it is seen as cheap...
But with regard to cleaning...I have not found any major differences...obviously if it is very old....you'll more than likely find a milky residue...but even that I have found can be limited.
Cheers
Dave.