Should glob.glob(...) be preferred over os.listdir(...) or the other way around?

If I'd like to create a list of all .xls files, I usually use

rdir=r"d:\temp"
flist=[os.path.join(rdir,fil) for fil in os.listdir(rdir) if fil.endswith(".xls")]
print flist

However, I recently saw an alternative to this, which is

rdir=r"d:\temp"
import glob
flist=glob.glob(os.path.join(rdir,"*.xls"))
print flist

Which of these two methods is to be preferred and why? Or are they considered equally (un)sound?