pdfcrop vs pdfnup --trim

I make heavy use of pdfcrop (the version by Heiko Oberdiek included in texlive) for printing, as it allows to remove all the white spaces around the text before nupping and printing. However, with recent ghostscript, the bounding box detection is dreadfully slow, anything from one to ten seconds for a single page ! When you have a 60 pages article to print, it can be quite tedious...

Well, I've just discovered that the --trim option of pdfnup can do very similar things too. It removes a given amount of margins on the side, with the syntax 'left bottom right top'. Most of the time, a well-thought pdfnup --trim ... will work as well as pdfcrop while in the meantime being much faster...