I am thinking about buying this book, so have any of you guys got it? Does he focus only on the x guard and the sweeps and submissions from it or does he also do some closed guard and diff open guard stuff like spider guard and de la riva guard or butterfly guard. I know most of the stuff will be on x guard, but i am just curious Secondly is the book worth it? does it go over everything in detail ? Thirdly where can i find a good book or dvd on the de la riva guard. Thank you all!