I like 16 week cycle. IF I was to cut with it, I would run something such as low dosage test (always have some test) at 300mg, 600mg primo, and half way through add 350 tren-ace (50md ED, 1/2cc) for last 8 week. IF I were to bulk/gain with it (I personally would choose other compounds for this purpose so this is just an idea), I would run 600mg test, at least 1000mg Primo, and while gaining can pretty much add anything you personally found works well for you. However, I personally use primo differently than either of these examples. I like to run it between cycles to hold the gains from the cycle but enjoy time without an AI or side effect etc. I run trt test at 150mg and add 300mg primo to that (it does not even show on trt doctor bloodwork). That extra 300mg primo is enough to keep most if not all my cycle gains. I cruise like this for 16 to 20 weeks between actual cycles -- enough time to get all health markers good and take a break from the health stress of my bigger cycles.