EMF data fromat

I`m curently use Epson C40UX (on Windows XP Professional) ,SiSoft Sandra 2002 "says" :
Generally you should use the EMF data format since it is faster and takes less space. Use RAW only if the printer (i.e. faxes) cannot use EMF, only RAW data format.
Can anyone explain to me ,which EMF I should use (there is
4 EMF`s ...NT EMF 1.003 NT EMF 1.006 to NT EMF 1.008)
Does EMF improve printing quality?
(sory on bad english)

 

Just did a search on google.com and found a number of hits using the search criteria "EMF data format ". That could be an alternative if someone here can't answer your question.

Tin