I created in a lot of work for Shredder Classic 4 and Fritz 13 GUI opening books for testing engines. This are not special books but all what is modern and can be play up to 16 half moves is included. All bad lines or lines I will get fast remis games are deleted. This was a lot of work and I used around 180.000 game material (40-minutes games).
I think with the results that we have a very good book for engine-engine matches with a lot of variants and a very little chance to produced double games.
Have fun with this work.
Can be found in my download area!