Exhaust exit location

Why hasn't anybody mentioned the 3 inch oval exhaust pipe to get past the factory gas tank??? Only $24 for two 24 inch pipes.
They also make them is smaller sizes. They also make oval 45 sections and 90 degree sections for snaking around corners that are too narrow for regular round pipes. Best part about all of them is that you don't lose any flow but you still get your exhaust going where you want it!!!
treblig