Have you got a big bore exhaust?

[Scythe13]

One MAJOR issue I'd have with that, being an ex Roy Bacer (haha, that's always funny, Roy Bacer) and tuning a 1.2 Nova to pop out 120mph and have everyone think I had a 2.0 V20 XE (Yes the Red-Top), I'd be more concerned with the knowledge that H2O was a major constituent of the exhaust fumes and wire wool and water makes major rust. Moreover, that same rust will be indiscriminate about the metal it goes for, Brilo-Pad or Steel exhaust. It could shorten the lifespan of your exhaust system. Better off forking out the £30 in the short run, that forking out £120 for a new exhaust system from the cat back.

Anyway, how long do you intent do keep the car? How often do you need to change the brillo's? How much does a cluster of Brillos cost? Might be cheaper to just take the £30 hit and go from there.

If you do go for the Brillo option, make sure you take it out for the MoT. It's an obvious thing, but it's easy to forget.