Just in my opinion after installing a whole lot of different uppipes wrxs I would say the gutted stocker is number 1. I havent found any drawbacks to it, the turboxs uppipe has 2 drawbacks 1 it isnt free and 2 it may leak. And Id have a factory catless uppipe as number 2 on the list (jdm or usdm uppipe).
And on the downpipes I would say the best one on a budget is a used hks that you can get for $90-100 shipped unless you happen to have a welder. If the price is the same why go through all the trouble of taking apart the dp and welding it back together especially since if you decide to change it you can sell the hks on the net for $10 less then what you bought it for, the gutted stocker wouldnt be worth the labor and money put into it.