A Buddy & I did a comparison of the 2 a few yrs ago.He had a 2-Liter Kelly Kettle,& I the Volcano.His was Whistling when Mine was just starting to bubble at about 3 minutes,Both of us were using 1/2 liter of water,with Oak tree trash for fire in mine,& Pellets for his.About 2 minutes later mine,Was on a Rolling Boil.I paid $20 bucks for 2 Volcano stoves-(New) His cost was around $140-(New)! I still have Mine,His got Stolen,Along with his Duluth Pack,& All his Patagonia clothing/Wiggy Gear in Yosemite,2 yrs ago!