I don't know the brand names that are available in Europe, therefore I can't make a recommendation. I personally use Morgan, Byron and Master here in Texas. I can get good synthetic oil fuel with 15% nitro for about 15.00/gallon (~4 litres) or in quantity of 4 gallons at $12.50 gallon. The OS engine manual will give you guidlines on what it expects to fueled with. If you don't have the manual, then [link=http://www.osengines.com]OS Engines[/link] should be helpful. I'd visit a local hobby shop and look for fuel that has at least 20% oil - synthetic only. I'd buy as high as nitro content as I could afford . . . . Sorry for the lack of specifics . . .

Regards,
Mark F. Sanderson