I have just spent a cold wet week with a top seated gas stove with no preheat and it DID NOT , boil 25L plus of water off a 240ml 220g net/370g gross cartridge , probably it would have boiled 10l if I had been careful . Had a multifuel and from a 500ml 350g net/450g gross white gas fuel bottle that is about the same size as the cannister , in the same conditions I achieved 14 litres of water , again probably more if I had been careful. So its a little more efficient than a heavy , cannister seated efficient cannister stove, two extra boils over all, or 80 grammes the extra weight of the multifuel. (BY BOILS I MEAN SINGLE USES INCLUDING SUSTAINED SIMMERING, AND LITRES I MEAN LITRE-ISH PANS FULL!OR USES) wondered if anyone else had the same sort of efficiency results to weight or any better performance .
p.s. I know pocket rocket equivalents are crap and useless !