I have a magnaflow fitted to mine, they are a great muffler and well worth the money.
My exhaust comprises of a 3" DP with a 100cel cat, a 3" mandrel bent stainless system with a magnaflow straight through style muffler, which then tapers down to the stock 2.5 small resonator & tailpipe (to keep noise levels sensible)
As far as the sound goes, it is not unbearably loud, and has fairly minimal drone, you can still have a conversation with passengers with the windows up, windows down and it is a bit louder, sounds good in cabin either way.
The note, sounds like a WRX & EVO have made babies, it has the WRX throb, with a bit of that nice EVO raspy bark mixed in.
I have uploaded some pics from the Best Mufflers site so you can see the system, not very exciting though, some 3" tube with a muffler jammed in the middle, and a sound clip I grabbed on the weekend of mine free revving in the driveway.
As with any good exhaust it sounds much better under load, although you should still get a rough idea of the sound.
NOTE: If you download the sound clip you need to change the file extension from .pdf to .mp3 ( I had to fool the forum software in order to allow me to upload a file of that size, and PDF was the only format that would support that size)
magnaflow.pdf