15% off all tyres at Tyroola.
I find Tyroola to be fairly well priced anyway, 4 Pirelli PZero Nero XLs for my car are within $50 of what I expect the price to be at MyCar with 50% off.
Don't forget that fitting costs extra. You can sort the fitting options by 'price ascending' when booking it in as it defaults to a mobile service which is quite expensive. Fitting 4 tyres at the cheapest fitter in my area is $108.
I purchased tyres yesterday and Tyroola were not in contention as their price was well over the price I paid. 15% off a higher price may still be too much.
MyCar were much higher again in price.