I was in this kind of position a few weeks ago and after talking to quite a few guys about it, I decided to go with a Dytech Blaster muffler, 2"-in to 4"-out. Muffler itself is $299, Silencer is $62.50, Resonator was $80 for 350mm and $99 for the 500mm, and the Mounting clamps were $36.50 each (and a good idea if you don't want any bars welded onto the muffler itself).
If you want to see what types of mufflers they have, go
HERE!
Some other people said to go with RPS Mufflers (at Pitstop, basic ones fitted for $350) but others said that RPS mufflers sound too 'tinny' so I decided against.
K<^-^>E