They are very similar. Some of the eq gains will generally dissapear, while the primo is almost completely permanent. I would not suggest running them both during an entire cycle. But if you were to use some test and eq, I would through primo in the last 2 weeks and carry it out 2 weeks past. It is a great steroid form helping you hold onto the gains from a cycle. If you want to use one in a cycle only, I would go with the eq because you will get a little more muscle gain, and it is far less expensive.
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