Some of us in the RDBMS world take it for granted, or that it is obvious, that SSD is a better way to go over HDD. The logic is unimpeachable: normalized data uses a fraction of the space needed by flatfile schemas, thus the $$$/database (not necessarily $$$/GB) is a wash, while the response is better for SSD.
Well, I've found an explorer who has had the opportunity to look at SSD and HDD with existing schema. Even in this less than fair comparison, SSD wins. He hasn't, yet, compared what I'll assume is a generally [un|de]normalized schema to the normalized version. Praise Codd.