slip on end can

[bri h]

So ive decided to go for the sp engineering XLS big bore on the groungs that if its good enough for kosmo its probably to good for me. Then i read that a shorter exhaust gives more top end power but less bottom end and visa versa for a longer can. Im not really looking for more top end power just a better sounding and looking exhaust. My problem is i dont want to loose any lower end power so the burning question is do i go for the 300mm (prettier) end can or the not to shabby 380mm one? Oh and the longer one is a tenner dearer.