I use the pre-stringing method for badminton racquets as I find it easier and actually more time efficient to do (although not necessarily faster). I can pre-weave the racquets in my spare time, say whilst watching tv and tension it another time.
With badminton racquets I also find that it is easier on the string when it is woven/pulled though untensioned strings as there's less friction. Some do find this annoying but think it's fine. Another advantage, esp. for badminton is that some shared grommets are very tight, and so are difficult to thread with a tensioned string already inside. There are ways around it, but in some instances these can be a pain to do.