don't bother with franklin's, lineups are crazy and thing about brisket is that sometimes it just sucks even at the great places (but not often). salt lick is great (byob) and there are a bunch of great ones out in the country. spend time and hit a few of those places up. don't spend your time waiting in line in a parking lot for something equal to what you can get in a shack in hill country. plus you get the drive and can see the towns and farmland. not the most stunning but still nicer than a parking lot near i35

i know more about iah bbq than aus but aus is indeed very good every time i tried out places there.
consult
http://www.tmbbq.com/

and realize a lot of those places in the top 50 are within 45min of austin