IMMX5

You're not spending more - nor has your consumption increased. The circumference has changed and thus gives both speed & odo meter reading variances which has changed your calculation... From memory I think you can recalibrate the computer for this (consumption) but not km's. Look at http://www.inawise.com/tyre-calculator/tyre-size-calculator.html, insert your relevant sizes and see the error (or the change in readings is probably the correct term)...

I won't touch E10 for the Lexus (and some of the other cars in the "fleet"). The alcohol is Hygroscopic (absorbs moisture) and tends to separate in storage - so even though there is supposed to be a max of 10% alcohol in the fuel there is no guarantee what %age is in the storgae tank at the garage. Additionally, the enrgy content is lower thus need to burn more fuel for equivalent 'performance' - hence higher fuel consumption with E10. I tend to use primarily Caltex 95, sometimes 98 - but to be absolutely honest I cant say the consumption or performance is any better with 98.

My windscreen was replaced by the dealer when I bought it - you wouldn't know it was a replacement (except for the scratch on the trim on the A pillar)! I had O'briens do my Mazda6 MPS a few years back - great job, no complaints. Another crowd was sent by the Insurer to do my daughters Corolla - windscreen fit was OK but there is a rattle from the trim. Most recently we were sent to another crowd to have a Holden windscreen changed. Probably the worst job of the lot with damage to the trim and some other ill-fitting bits.

I've noticed a rattle - only when left in gear & waiting at the lights... No such rattle if you slip it into neutral. :) I've yet to experience a service by a Lexus dealer - what has been the response when (if) you arrive with your own oil for the oil change?

Guess you do get a glare sometimes - obviously depends on the inclination of the sun. Wear some good sunnies. I would n't put a dash mat on - you don't want it to compromise any of the airbags should they need to be deployed...

I'd guess a slight improvement had we had 20C temperatures - the big difference is between the 250 and the 350 motors.

I have Dunlop SportMaxx Sp on the car - very ordinary drive and VERY noisy. Has anyone had experience with Michelin Pilot Preceda or Pilot Sport II's? Have the former on my MX-5 and they are superb wet & dry, road & track - and certainly not noisy...

Trip from Sydney to Melbourne (arriving with a temperature of 46C) I managed 7.5 l/100km (I zeroed the computer at filling up immediately before leaving Sydney). Return trip measured from Gundagai to Sydney was 7.5 l/100km. Prior to the Melbourne trip I normally averaged 11.0 l/100km incl. (with the wife driving). My current tank is 9.6 l/100km and the average since originally leaving for Melbourne in mid January is now 8.7 l/100km - and driving style may be regarded as "spirited but smooth driving" - and avaoiding the peak traffic as best as possible)...