If I didn't already have the Nismo 370Z with the racing cat back exhaust and factory engine performance tuning, I would add an Akrapovic system to it. The GTR kit is crazy.
They have awesome Porsche, BMW, Audi, Ferrari, and Lamborghini upgrades as well.
The motorcycle exhausts are so much more expensive than the car systems due to the use of more Ti and carbon fiber. A car can afford the slightly heavier SS headers since the overall weight of the car and power.
Since we measure upgrades in grams not kilos, demand higher performance gains for minimal changes, and those welds, expect to continue paying a premium.
If you want Two Brothers for your Yamaha, then you will spend less. However those systems will fit a very wide range of bikes. One exhaust will fit anything in two models years of Honda, Suzuki, Kawasaki, etc.
That Termignoni and Akrapovic will fit Ducati Panigales and that is it. More expensive for R&D, fabrication, and inventory management.
Don't tell me about Austin Racing or SC...
2014 Panigale 899 - Red
Termi Exhaust, Rotobox Wheels, NRC Fender Eliminator, Rizoma Rearsets and Reservoirs, Yoyodyne Slipper Clutch, Ducabike Clear Clutch Cover, CRG CF Levers, DP Fuel Cap, 'R' Seat Cover and Decal Kit
R&G Radiator Guard, Fork and Tank Sliders
2015 BMW S1000RR - Red
HP Wheels, Akrapovic Full Ti GP Exhaust, Competition Werks Fender Eliminator and Integrated Tail Light,
Rizoma LED Indicators, Fuel Cap, and RRC Levers, Bonamici Rearsets, R&G Sliders.