Helix 3" polished Stainless, cast bellmouth, no cats, center glasspack resonator and large straight through can at the back... you could drop a tennis ball in at the bellmouth and it would shoot out the end (Hmm... sounds fun, now how could I rig that up, lol). I payed $450 for it... just gotta love WRX hand-me-downs.
The pipe extender is not stainless, 4" long section of 3" pipe and some flanges I made from 3/8" plate. Also made a thrid gasket from very soft 0.075" aluminum sheet, I've done this before and it works great.
I had to twist the hangers around quite a bit (used the torch). And all the bending in the world wouldn't make the foward hanger on the axle back reach so I built an extension like a U-bolt to reach down to the hanger. But I think some people just dont use the that hanger.
It might have worked out as well or even better if I had put the extension between the mid and tail pipe.
Its pretty loud

On the up side... the tone of the pipe is simply beautiful, very low and a great growl, the sound at 6000rpm full throttle is nothing short of spectacular. Power is up across the board, turbo spools faster and the engine breaths better in the top end, widened the useable power band quite a bit. And seems to have picked up a mile or two per gallon in fuel economy.
Pics...




More Pics here:
http://photobucket.com/albums/v204/All_talk/Subaru/?
Gary