I'm going to throw in my two cents here. I've had a s/c Tacoma in the past and currently have a s/c'd 4Runner. The thing to keep in mind is that exhaust diameter is more crucial in normally aspirated engines. There are tons of posts on the web about the subject. A supercharged engine is a completely different animal. Since you are forcing more air into the engine, you need to remove that air much more quickly. I would say that your lack of low end power is more a combination of fuel and timing. Before you go ripping off your old exhaust, I would put the money into a fuel system upgrade. I know that people will argue that a stock 3.4L engine will adapt to a S/C just fine. Heck, my Tacoma ran absolutely tip-top with the just the s/c and no fuel upgrades. However, my 4runner runs 5 times better with the fuel upgrades. By better, I mean more low end torque, winds up faster, and just plain pulls harder.

My advice is to invest in the URD fuel kit for your truck. You'll be amazed in the difference it will make. Good luck with your decision, and let us know how it turns out.