I agree. Using a chop saw (otherwise known as an electric miter box) works great. However!!!!!
Be sure to add on an auxiliary fence, with a very narrow "throat." I've had several instances where a less than perfectly straight piece of wood was pulled into the "throat" by the blade, resulting in a bind or severe kick. Keep those fingers clear and far away in case the wood is yanked hard. I finally had a kick so severe that the wood was yanked, bound up the blade, and bent the arbor of my best miter saw, ruining it. :doh:
The safety issue ought not be ignored, even by the "experts" - I had used that saw for well over thirty years professionally. Making an auxiliary fence will not make it perfectly safe, but will help immensely. Usually this can be accomplished by screwing, bolting, or clamping a 1" x 4" across both fences, then carefully lowering the blade through, creating a throat a blade-width wide. Even then, be aware that the blade may still want to pull the piece of firewood in its own direction, but with a narrower throat, it will have much less room to kick so severely.
BTW - to be safe, NEVER cut a piece of firewood once it gets less than 12 inches long - your fingers are way too close to the blade and uneven firewood is too inpredictable! Only attempt such a cut if the workpiece is solidly clamped and your fingers are far away.