Actually Bluestang, perhaps you can help me with something.

I found a brand new VT64, but it's one of the newer ones with 1.7FW. It was at 97 percent MWI out of the box. I tried D flashing it again, but nothing happened, so I flashed regular Vertex FW, used the NAND cleaner, then did Vertex Turbo FW again. This time, all the factory blocks disappeared and MWI went back to 100. But after a few moments MWI dropped back to 97 as the bad blocks got flagged again. I didn't know MWI was affected by runtime bad blocks. I'll post screenshots tomorrow.