mainconcept convert time for 800mb avi is about 10 min dvdlab pro authoring about 10 min if you want just to push a button ,fancy authoring time depends on you
the softs like nero take hours ,rendering engine terrible
lot of avi convert with 1 click buttons don't even work
another good convert is tmpgenc at times a little faster than mainconcept
there's a freebe at sourceforge that does converting just as fast ,but I have not bothered to learn it,can't remember name redub or virtualdub or something like that
I'm happy with what I got