My current track toy - a Toyota Supra Mk3 - came with an exhaust system that was fitted by Top Gear (another branch, not Battersea). I was seriously unimpressed, not least because it failed noise tests at all the circuits I visited.
Here's what I found when I decided to have the system replaced: the rear box was, by all accounts, empty of any meaningful packing, and the stainless steel pipes were already rusting after 12 months. Also, rather than bending the pipes to suit the chassis, it'd appear that the fitters decided to chop and weld several bits together. I have no problem with that, but at least one joint was not properly sealed, so the year-old system was actually blowing.
Your "reasonable quote" is most probably down to the material/workmanship they offer there...like most things, you get what you pay for!
If you want someone to do a proper job for a sensible price, I'd highly recommend getting a custom Magnaflow system from Profusion Customs -
www.profusioncustoms.com - they are near Heathrow, just off the M25. You might even get a discount if you tell them "Andy with the track-prep'd Supra" sent you. [
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