I've tried it and compared to E20 and 95 Gasahol there is no apparent difference in performance or consumption.
There IS of course a vast difference in price. At 22 -23 THB / litre it is a positive bargain and on a full tank I can save up to THB 500!

So - here is the problem.
I know of only two garages (gas stations) currently selling the stuff. Both are on Rama 11 Bangkok bound and are 'Lemon Green' branded.
I know that PTT are gearing up to sell the stuff and where it's advertised the price is always 00.00. Meaning that they are not yet stocking it.

So my question is - does anyone know of a garage near to Hua Hin currently selling it?
