You should really listen to them. To give you an idea. My friend has a 5.5HP clone minibike with A TAV2. My other friend just got one with a 6.5 Clone and centrifugal clutch. The bikes are identical and my friends weigh about the same. They had a drag race. Even though the NEW bike has more power and is brand new with just some brake in miles, it LOST horribly. It had a surge of power and then it topped out. My other friend with the TAV2 kept pulling away until his maxed out at about 40mph in overdrive. He won by such a large margin I couldnt tell you how many bike lengths. We ride in groups, where 1 goes the other follows. He tried to keep the centrifugal clutch on that bike all summer but it burnt out the first 3 days trying to do what we can all do with our TAV2's. (and have done for 2 years).
But in the end just have fun..... that's really all that counts