Just rolled over 15k miles so thought I'd post a mini update. Long term mpg for those 15k miles stands at 26.7mpg on Shell or Texaco standard unleaded. The car is going to my local detailer in 3 weeks time to be stripped back, any defects corrected and Kamikaze ISM Coat applied. The CQuartz Finest lasted well and is still in evidence but there are quite a few defects needing attention courtesy of a run in with a bush and my works car park!
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@Bristle Hound I just can't resist trying new stuff. For now a quick Reload topup 3 weeks ago is tiding me over.
@Scottyg loves this stuff and it is indeed good. However I have a slightly dodgy batch from 2014 which smears like mad even diluted 50/50. I've used the rest on the wheels which works really well and is a doddle.
Other random stuff. The radio has taken to forgetting that it was left on so that when I come back to the car and start it, it's off. This seems to happen most when playing media from the SD card and turning the ignition off. I need to try and pin it down but not really that worried.