hmmm had blue flame and quill,blue flame looks the best and sound ace even with baffles in however if i had to choose i'd go for the quill its not as loud but sounds a lot tighter and raspier the engine feels better and the build quality is wayyyyyyy better than blue flame..saying that i never had a problem with the pipework discolouring on the blue flame as it does on the quill..nahhh its still quill everytime
