Hey Jeff,
Glad to hear you're having better luck with it. One of my early projects with purpleheart was trying to turn a 10" plate out of 4/4 stock. I had a minor catch and the thing split right in half! I've come to the conclusion that purpleheart will either grow on you or you'll hate it. Most people don't have any middle ground with it. Same for a lot of woods, I guess.
I like turning jatoba, aka "Brazilian Cherry" (although it doesn't look a thing like cherry, AFAIC), but I usually hate the end results because it warps like crazy after it has been turned. I frequently have had it twist out of shape _as it is being turned_! It's a pretty wood, and as you say, dense, but too unstable for me. I avoid it unless I have to do a display piece out of it for my lumber folks.
Absolutely. And if you can always burn the results and nobody will be the wiser, and if you get a nice finished product, so much the better! I'm always raiding my father's firewood pile, although lately he burns just ash, so there's not a lot of variety, although there's some nice figure in a lot of it. Very curly stuff.