I'm on my first cycle. It's not having the diuretic effect on me that it has had on some, but honestly, that's probably a problem in and of itself- I'm likely not drinking enough to begin with.
It's too soon for me to comment on the final effect, but I will say that it gives me a clean sort of endurance boost-- i.e., my old "pushing it" is now my new "not enough effort." I don't feel any sort of stimulant or appetite suppressant.
I'm really happy so far. Honestly, the boost in the gym and out on the trails blows my mind. It may be entirely mental, but that's fine-- if my mental is now starting to positively affect my physical, I'm kosher with that.