These trees and grass are double sided so you can use any shader with alpha and both sides will render. Current images show the built in diffuse cutout shader. This causes the triangle count to be double but I have read that this is a better way than forcing the shader into running a second pass to render the back side of single sided faces. If you disagree with this or have more information please contact me and let me know.
The vertex normals have also been bent so the trees and grass will respond to real time lighting changes without weird lighting effects.
I will be updating this pack with new content in the future so purchase with confidence. The price is never going to go on sale and will only increase when more content is added.