I cook over a wood fire most of the time.  Occasionally I have to take a stove due to fire restrictions; and I'll have to say it is nice to have a quick and hot meal on a wet day.  I usually travel every day but don't think the fire building takes a lot of time and I can usually find dry wood.  Sometimes campsites which are almost wood-less will have beaver wood along the shorelines under the brush...lots of campers don't use the beaver wood approach.  If it is wet and late in the day I sometimes just eat cold items but really miss a hot cup of coffee.  Cooking on the BW grates can be difficult, they are too high to be able to cook on a small twig fire, so you have to find quite a bit of wood to get a hot fire going.  I bring along a small camping fire grate and build a little fire just in front of the grate area, balancing the grate on a couple rocks.  When done I just shove the coals back into the fire pit.  When going with 4 or more in the party we usually bring a two burner camp stove, it makes cooking for a group so much easier.