I've ran a shit-ton of Eq over the last 20-25 years, and I can say that if you get water retention or even nipple sensitivity, you probably got fake eq, which would be apparent to ID by the source as it is in liquid form in the raw.
Not a big fan of Eq after all those years, just not a big responder myself, I always just added it in because, well, it never hurt anything, and it brought out more veins when cutting, and some strength. Outside of that, I never got much. I have seen some guys respond very well to it, so it will be individual like all compounds....but generally, not a lot of weight gain, but solid hard gains will develop, along with a positive enhancement in look, especially when incorporated in a cutting phase.
Don't want to say it's side effect free....keep an eye on hematocrit levels, some acne, panic attacks for some, and maybe BP issues if prone. No gyno or water retention.