I used Sky for my renewal last month. £30 cheaper than Flux and £200 cheaper than my renewal with Admiral and much lower excesses too. Monaro CV8 inc exhaust mods.
Adrian Flux for me after being insured with sky for a couple of years they quoted me a very significant amount cheaper with all mods supercharged, cam, exhaust, brakes etc etc. Plus agreed value. Must of just hit a sweet spot with them.