Tren by far. Will knock your socks off. This being said, what is your cycle history and what compounds have you used before? The problem with Test and Tren alone is that it leaves the joints, bones, tendons, ligaments, etc, vulnerable to injury because of the amount of strength you are gaining and the muscle you are putting on in such a short period of time. Read the sticky on collagen synthesis. its good to have a steroid in the mix that promotes this, such as EQ or anavar.