ram74,
As others have said and others will tell you...You really should install some kind of system that will allow you a adjust the fuel/ignition system on your Warrior, after you install an aftermarket exhaust. Whether it's a Power Commander III or some other model...You'll find that the Power Commander III is just about the best unit out right now.
Anyway you can also try tweaking the stock ECU that is on the Warrior. There is a or a few topics in regard to how to do that somewhere here.
One thing about the Power Commander III is that you can go to the Power Commander website and download maps for the Warrior and install them on your PCIII. Just find a map that is close to the set up that you want or will be getting, and download that map then install it on your PCIII. It's pretty easy and Power Commander provides you with all the software to do it. Plus, you can go to the tech help section, if you have any problems or questions. They have always been very responsive and helpful when I contacted them...
Also if you do go with the PCIII, I highly recommend that you do the "Perfect Install"...It definitely makes a difference...After I did it, my Warrior smoothed out in idle, had a better throttle response and was more crisp. Definitely made the bike run better...
There is a topic in the Technical Discussion section that has complete how-to on completing the "Perfect Install".
Well...Hope I helped and best of luck!
Mark aka Mad Man