"vortex2" wrote in message
...
Out of complete curiosity I filled my car with 99 octane petrol at Tesco
the
other day.

See http://www.greenergy.com/products/99_octane.html

99.9p/litre versus 95.9p for 95 Octane. Basically I suppose the same
price
when measured in "pence per octane"

My car (5 year old Volvo) has never run better.

I've yet to see if there's an economy benefit (I'm sure there will be).

If yours is a turbo then yes you will find a marked improvment in
drivability and go. Volvo turbo's are renown for needing 98octane or more to
give their best.

MPG should be better by a couple of mpg too, as long as your driving style
is the same.

Tim..