Cypionate and Enanthate are almost identical. Enanthate is only 1 carbon atom lighter. Anyone that says they can tell the difference in the 2 is crazy. When it all comes down to it once its in the blood it all does the same thing. Its all about what kinda cycle your running and for how long. And as far as a rapid mass builder, Test Suspension hands down. I like longer more steady gains so I'm a big fan of Cyp and Enanthate.