I have had my 2003 black Marauder (AKA Mr. Vader) since I drove it off the showroom floor 5 years ago. It has always been much faster than any other car I have driven.
As a result of favorable postings on this site I contacted Reinhart Engineering about an SCT XCAL2 tune which I understand adds about 27hp and 30 pounds of torque.
Dennis Reinhart, himself, talked to me and answered all of my questions before and after the sale. The customized tune was provided at no extra cost over the base $379 for the SCT unit (which was the lowest price on the internet anyways).
This tune is MARVELOUS!! Mr. Vader is now much more spritely and quicker around town. The shifting is much smoother and precise. What really impresses me, however, is passing some slow poke on the freeway. Going from 45 to 90 mph is dramatically faster! All 32 valves seem to open up much sooner and give me a real kick in the ass acceleration! The engine sounds like it has a turbo charger opening up. Much like my 1987 Toyota Supra Turbo did, but with a lot more power.