Some personal bloggage on the topic:
In my travels I can't see how to justify using them seeing as I got my bike for maybe $350 including locks, lights and helmet.
I sure hope someone doing research with homeless populations has begun to look into questions of whether or not the flood of bikes into markets has improved conditions for homeless folks. Social services can be hard to get to, and I could imagine these bikes serving a valuable purpose.
I also wonder if the flood of trivially thefted bikeshare bikes has reduced theft of other privately owned bikes. Presumably at least some bike theft is to satisfy a transportation need. If there are limitless Ofo bikes that nobody gets too fussed about when they go missing, perhaps someone is less likely to go prowling a garage?
Obviously, the bikeshare companies roll out their newest stock in Beijing and Shanghai. I'd guess most Ofo bikes in all of China still use the manual unlock, and will do so for a while yet.