I dont know of a bad smell from burning, but I love the fresh split smell. Ive been quite a bit the last two years.
To me, black locust smoke smells a lot like rotting grass, not especially pleasant but I haven't noticed it after a burn gets going well. Like any other smell, half of your response to it is what you associate with it. I have a friend whose father cut a lot of firewood when she was little, and to her the smell of black locust is the smell of childhood.
I'm told this is honey locust. I have some help coming in a few hours, and we're going to haul firewood until we run out, or are too exhausted to continue.
Good for you for getting after it. You'll see the density when you start moving it --I've only burned black locust but honey is some of the best firewood out there, too.
I cut a thornless Honey Locust down out of a yard in town for a guy. It is heavy when green, I split it and had it in a stack for 2 years to season. It burns nice, the big issue that I had with it, was being in the stack for 2 years the powder post beatles found it. I had to sweep tons of saw dust off it to bring it in the house.