In response to your question on availability in commercial HDs, I think that unless a comparable significant advance is made in read speeds, I doubt that you will find it in consumer grade HDDs soon. A disk that can read at e.g. 100mb/s and write at 50gb/s would be not easy to sell to the consumer at a premium price (where do I get data faster than my HD/SSD read speeds from to store?).

I assume though, that it might be used in e.g. CERN, where they need to store a ridiculous amount of data in very short time. Or similar activities where the write speeds are the limiting factor.