BMW x5 4.8is (e53)- X-pipe or Straight Pipe?? PLEASE HELP

[BMW-x5-48is]

Hey Guys,

I am removing the resignators on the my 2006 bmw x5 4.8is to give it a more aggressive sound. I feel the stock is good but can be alot better. I like mean sounding machines - like the oldschool Ford Mustang Cobra.. Love it!

I have to options to go with - either a 1.) X-Pipe or a 2.) Straight pipes

I look around the net & people claim the Stright Pipes is the most aggresive sound you can get - others say its too much as it sounds like a Machine Gun. In addition people state using stright pipes does not create backpressure & torque can drop. Others say to use the x-Pipe as it still sound great, but filters some of the unwanted sound & creates back-pressure which helps torque.

If you guys had/have a 2006 BMW x5 4.8is -- which option would you go with?? STRIGHT PIPES?? or do a X-pipe???

Please guys let me know which I shoukd pick.. I love aggressive sound - but if it sounds retarded I dont know if I want it.. Let me know which one you guys would go with... .. Thank you so much for your input.. its greatly appreciated....