Thanks for all the replies. I've been lurking here for a while. Your forum is informative and helpful.
I do plan to get all three working properly before I make any decision. It wouldn't make sense to keep one that's not functional. Besides they are worth alot more in working order.
The grizzly lathes are unused, came from the scratch and dent sale and never unpacked or hooked up.
I plugged in the M1099 and the motor starter clicked but motor didn't run or buz. I expect it's either bad wiring or motor starter. I think this lathe will be the easiest to sell because it's a 110V plug in bench top model.
I haven't tried up the G0791 (gunsmith lathe). It has never been wired up yet and requires 220V. It has an obvious problem, the milling attachment is broken where it attaches to the lathe. It appears to have been that way when he bought it because it has strapping to hold it in place. It came with a 4 jaw chunk in addition to the 3 jaw installed. I like the separate threading and power feed shafts. It's extremely similar to my old harbor freight lathe with the same style casting, controls, casting etc. I'm pretty sure they are the same base model built at different times for different customers with different options. If I keep one of the Chinese lathes, this would be my preference.
I actually want a small lathe. I sometimes need to work on small parts and a 6 to 9 inch lathe would be appropriate. I'm not in a production environment. My lathes are seldom used. I'd love to have a nice South Bend 9 but the atlas came up at a good price.