M Power installed my Challenge HFC DP yesterday and I have to say I LOVE the results! The sound is amazing and I feel a little extra oomph in my power. The turbo whistle is sooooo nice and the exhaust rumbles and crackles quite nicely. The upshift burble is also more pronounced! All things add up to equal a VERY satisfied driver
I'll try and get a decent video or audio clip of it. I haven't managed to capture any good-quality clips with my phone...too beastly!!!