I've had a set of Marks Pipes and the sound is incredible!
You have a couple of options in moving forward. If you have the cash to spend and want to maximize the horsepower potential of your bike you should buy a jet kit. There are really only two choices out there that are worth while.
My #1 choice (and many others) is a "Morley Muscle Jet Kit" click on the banner at the top of this site, or look around and you'll find tons of info. The jet kit will get you the most HP out of your OEM carbs, the best mileage, and Sean has the best customer service out thee.
MY #2 choice would be the Dyno Jet Stage 7 kit. It will give you the same HP as the muscle jet kit but you will lose some low end grunt, it costs more, you lose your airbox in lieu of separate, pod filters, and say good bye to vboost.
If you don't have an extra $250 to spend on your carbs after dropping the cash on your pipes, DON'T WORRY!:biglaugh:
You can get your bike to run just fine without a jet kit. All you need to do is buy some small washers to shim the needles and turn the A/F screws a bit and you'll be good to go.
I was intimidated by the Vmax carbs when I first bought the bike but with help from this site, I gained the knowledge and confidence to totally tear into them with great results!!! There is a wealth of knowledge here in the carb forum. Lost of great posts and pictures to help you do the job right without having to pay a dealer to screw it up for you.