redstone generators are 320 rf/t each, while the best consistent output you can get with coal is 80 rf/t afaik, that other weird furnace generator that burns at random numbers based on how much fuel it has or how long it's burned or I dunno what never made a whole lot of sense to me. It's kind of a pain to "take land" in crash landing and make it safe so I usually treat size as an important factor.
As far as culinary generators go, tbh I don't even know how they work. I suppose you could shove a ton of supreme pizzas in there if you had a large enough farm or enough bonemeal, but it seems like a hassle without AE automating it, and if you have AE automating it you should already be established enough to not need power, heh.