In reply to Paulos:
> So I take it that the advantage of models like the MSR whisperlight or primus multifuel is that you can burn anything like petrol from a shell garage or white spirits from supermarket??
Somewhat, mostly people use Kerosene/paraffin, white gas (coleman camping fuel) or 4 stroke alkylat fuel ( for lawnmowers chainsaws etc). These are the main recommended fuel types, are the cleanest, most efficient and safest.
Diesel is ok but smelly, its a love hate thing there. For Petrol, low grade (the cheapest?) is best for these types of stoves and should really be considered a last resort. Petrol from a petrol station has a lot of additives that can clog the jets, rot rubber seals, or have ethanol mixed in that can corrode the fuel canisters, but will work well in terms of cooking.
White spirit doesn't work very well at all and it doesn't burn well without a wick, so is not recommended! You cannot use alcohol (methylate) in these stoves safely either.
But put simply yes, you can fill up the fuel bottle at a station (assuming there is no minimum sale quantity) and off you go. Kerosene/ paraffin lamp oil is probably as widely available as diesel, but often sold by the bottle (more convenient), if petrol stations don't have it, hardware shops will. 4 stroke alkylat stuff should be pretty easy to come by at a petrol station and I've found it is quite common in rural areas where there are a lot of farms.
The real advantage is that there is a wide range of fuel types and they are often available at any time of day, anywhere. So you don't have to worry about eating cold when you pitch camp at 2am.
> That would be ideal for me and make it worth the extra cost. Do these have downsides then also??
The downsides are generally; the weight, the stove gets dirty, smell, needs good maintenance to work well, can't be primed inside a tent (but stove can be moved inside afterwards if you dare), require a bit more thought to set up, need to be pumped to get pressure. In addition I've also found that you get less choice of heat/power if you want to warm something slowly. Its really a hot or off option, but this is with old stoves so new ones are probably better.
These stoves also need to be 'primed' before you can cook, where a small amount of liquid fuel is burned to heat a dissipator. This then evaporates fuel to gas that is subsequently burned as a blue flame. So its not a simple screw it together and fire it up job.