In reply to Jus: I have one like you have linked and to be honest, they do the job well. Perfect for leaving in the back of the van for a quick brew, bit of breakfast, soup, hot choc when you get back to the car etc. I use mine when car camping as well.
The gas is really cheap for them.
I have a Coleman petrol stove (double burner) and a primus omnifuel. The briefcase one gets used the most as it is so convenient.
The only time I find it utter rubbish is in the winter. The gas doesn't like to be cold. £11 is a good price, shop around for the gas on ebay.