Louder isn't always better, but to achieve power, louder is a byproduct that can't be avoided. The difference comes when it is excessively loud. Simply taking out the baffles in the stock muffler will not help power, in fact it usually hurts power. A motor is basically a pump. The better it uses the air it takes in and expels out, the more efficient it is and the more power it produces. There are a number of factors to make this happen, but generally speaking, putting in more air and getting rid of it faster will create more power. The motor is controlled combustion. To create combustion, four elements are necessary, fuel, air, heat, and the chemical reaction. Engineers attempt to create the perfect environment for this process to occur. Changing fuel levels and ignition timing can aid in this pursuit, but giving the process more air, fuel, and heat increases the output of energy which translates to more power. Installing an after-market air cleaner that allows more air-flow is the first step. Installing an after-market exhaust system that will expel the air and gases quicker than the stock system will produce more power. Installing a power-commander or equivalent allows the process to be calibrated and balanced to produce the most power and most efficient use of the air, fuel, and heat. We are biased (for a good reason) and prefer our MGS True Duals to accomplish this task. When it comes to sound, it depends on the rider, but the riders who have installed our exhaust systems have been overwhelmingly satisfied with the deep-throated exhaust note that is loud when you want it, and not when you don't at cruising speeds on the open-road. Go to our website and click on the video of the True Duals install to hear them for yourself.
Ultimately, enjoy your ride the way you want it, nobody else's opinion matters. If you're happy with the sound and power from your bike, than it is right, period.