As I seem to have ended up with one of each I thought I’d compare the two. The Jetboil is a popular thing and consists of a pot with heat exchanger, burner unit, lid and protector for the heat exchanger. The set up, without gas canister, weighs 414g. Packed it is 180mm tall and the maximum diameter is 108mm. The Primus EtaExpress is shorter and wider at 150mm tall and 120mm maximum diameter when packed. It is also a little heavier at 472g without gas canister. The Jetboil fits together as a single unit with a neoprene insulating pot sleeve, whereas the Primus is basically a standard folding stove unit with a heat exchanger pot, small pan/lid, and windshield. The Primus burner is larger than the Jetboil, and comes with a protective pouch. The Primus packs in to a net bag, whereas the Jetboil just packs in to itself. Both have piezoelectric igniters. I boiled 500ml of room temperature tap water using each of these stoves. The Jetboil brought the water to a rolling boil in 3 mins 56 secs and used 6g of gas. The Primus did it in 1 min 44 secs and used 4g of gas. The Jetboil’s neoprene sleeve and protector for the heat exchanger are both good ideas and missing from the Primus. However, the Primus more than makes up for these design differences in flexibility. The Primus may be used as an ordinary stove. The wider pot means that a 220g gas cartridge may be packed inside it instead of the 125g cartridge that fits in the Jetboil. Alternatively, I have found a stainless steel Tatonka folding handle mug will fit inside the Primus pot, with a 125g gas cartridge inside it, making it even more flexible. For use with a motorcycle, I suggest the additional 58g weight of the Primus is negligible compared with the improved flexibility and efficiency. Both appear well made, although I think the Primus just has the edge here, and both cost about £60 in the UK.