It would be nice to have links to the datasets and scripts used, so that others can reproduce the tests.
Done.
It's surprising that the search time differs so much between the point_ops tests with uniformly random data with 100M and 10M rows. Just to be sure I'm reading it correctly: a small search time is good, right? You might want to spell that out explicitly.
Yes, you're reading this correctly. Detailed explanation was added to the wiki page. It's surprising for me too. I need some more insight into causes of index quality difference.
Now I found some large enough real-life datasets (thanks to Oleg Bartunov) and I'm performing tests on them.