While testers gravitated toward the Firefly's rounded, smartphone-esque design, they were left unsatisfied. Despite its clever features — a magnetic lid that makes packing easy; a powerful, 400-degree convection element that heats up almost instantly with the push of a button — all of them agreed it was bulky, imprecise, and, no matter how it was packed, incapable of producing a good hit. [$270;]