So I started a longer-term test of the MOBI 3000 to see if it's a decent test candidate. With 3GB of static data and 2GB min free space, it's averaging 53.99MBs over the past 9 hours. I'm not convinced the one smart attribute's raw value is in fact erase count, but if it is, it's going to take a long time to deplete MWI.
After 9 hours, the "erase count" is up to 4,010,600. When it hits 160,000,000 MWI should decrease from 100 to 90 -- which should happen in 360 hours or 2 weeks. Multiplied by 10, it should take 20 weeks/140 days to deplete MWI if the erase counter works as suspected. Assuming it lasts 3x longer, it could take 420 days to kill the drive.