K1 is renound for being a cr@p piece of kit. Scorpions are ok at the budget end, I think they had some production line issues a while back but these have been ironed out. 
  
Mine fitted perfectly and 10000 miles on, it doesnt miss a beat despite being on and off a few times. No vibrations or catching on subframe etc  
  
Only thing I didnt like was the tailpipes as they are slash cut, so I swapped them