i wouldn't go with the smart parts barrel, only because you can find better, cheaper (at least for the performance).
i would go with the CP one piece, the bore sizes have been proven most accurate and are very cheap.
here is the link:
http://www.xpaintball.com/spydonclasba.html
or if you can find a CP two piece those are great too. after you get some more cash i would recommend the Dye Ultralite Barrel. very light and accurate.
but if you had to go with one of those i suppose go with the All American.