If you want some real deal OG dank then go see Cali Connection or OGRaskal. From experience I can say these are the real deal OG. Not a cross but about as close to the real deal as you will find in seed form. I am currently growing CC's Larry OG Kush and it is simply amazing. Again, these are about as close 100% as they can be. I am not going to get into the way they were breed but here is a link if you are interested.
http://www.thcfarmer.com/forums/f90/my-breeding-techniques-5914/
I can assure you if you decide to get either of these beans you will find a mother per pack that will stay in your garden for years to come, it's that good.
I have pics if you are interested after reading the breeders technique. Good luck and go give'em a try. You will be glad you did.