I was keeping a notebook for a while on the 'net weight after draining' of browned ground beef, I find that the 80% often seems to produce a lot more fat than 85% does. 93% is a bit more consistent, you can almost get it to a dry state, not that I think that's a good texture for food, and 93% makes for dry and almost tasteless burgers.
My point on today's question was in part to note that if you're careful shopping you get pretty much the same 'per net pound' cost regardless of what fat level you buy, so other considerations may be more important. If I'm making a meat loaf, I will usually go with 85% lean, because 93% won't hold together, even with other binders in it. For something I"m going to drain anyway, I usually stick with 80%.