Hi keith……..I use a Colemans stove with unleaded petrol and love it(fishing shops seem the best stockists)………Colemans do recommend their own fuel but petrol is fine. The issue is using petrol for the stove and the outboard and at what point you mix in oil (my 2 stroke uses 50:1). As a veteran of two overnights (!) I just took two separate gallon tanks (one petrol one mixed)on the basis if I need to make up more outboard fuel I can, but I wanted a decent amount already mixed up in case of needing to refuel on the open sea where spillages or contamination while mixing want to be avoided. As usual I never even needed to top up the outboard. Dave