Yeah the can is superb. Hard to say if its increased the power but the sheer noise makes it feel a hell of a lot faster

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On the stock exhaust I felt the bike was a bit stifled and didnt want to rev so much, but with the new exhaust on it feels like it revs a bit quicker and has a bit more urgency. I'm not good enough to tell if it has increased power, but for £100 my bike is transformed, so I'm a happy man and would thoroughly recommend getting one while they are going cheap!
Oh and the best bit - if you happen to hit the rev limiter when you are giving it some stick, you get a nice, loud backfire that scares the crap out of dozy car drivers, fantastic