Smoke has reviewed them on this site, so have other people; though that may not do you much good unless you ask to see all the posts by Smoke--a feature of the forum up to 200 (?)posts per person,-- and it comes up.
Many thought it was pure gold, indeed.
IMHO, Keating has made far better tapes. The Conceptual Gold takes 5 moves from Kali and 7 from Silat (or was it the other way around? I gave my copies away as a gift months ago..)
and milks it for 3+ hours.
The equivalent of a Karateka taking the first 5 moves in a Kata and linking it to God, the universe and everything, or a boxer going on about a jab cross combination while speaking very, very, slowly to make it last a long time on tape.
Save your money.
And yes, The Yakuza is awesome. If you can get that pesky recall feature to work, there was a thread of 'favorite movies', or some such heading, a while back in the Community Forum where it recieved high praise
Good luck.