Different people react differently to the same compound but I can tell you about my experience with each. I did not care for phera. It did put size on but it was very wet and the strength increases were minimal for me on phera. Halodrol gave slow steady gains for the entire 30 days I took it. It did cause considerable strength increases without all the water weight. Superdrol was more powerful than either of the previous two. It led to size increases and suprising strength increases. It had pretty harsh sides but I still didn't want to come off it because I was enjoying the increased size, strength, and endurance.
If you don't have experience with these compounds, please make sure you research the forum for things like post cycle therapy, support supplements, and dosages. With these, a little is good but more is not neccessarily better.