I played around with my heated print bed and Kapton tape again. I did a few prints and it was OK, but challenging objects just failed. In particular, the LM8UU bearing holders for the i3 have an overhang and I just could NOT get it to print properly. Not only did the overhang cause the piece to curl up and whack the nozzle, as the nozzle whacked it, the heated bed caused the PLA to be soft enough that it got pushed back and forth so the layers wandered all over, and eventually the head picked the entire piece off the print bed.
I put blue tape down, turned off the heat and got a beautiful print.
Here's the failures next to the successes. You can see on the failures that the layers on the overhanging bits (toward the top of each piece) are inconsistent and just generally horrible.