i'm pretty sure each one works differently
i've used EQ and primo
and will tell you that primo will give you nothing but lean muscle with little to no sides
no anxiety, no blood pressure issues, no loss of libido, no loss of hunger
and it keeps you lean provided your diet isn't retarded and full of mcdonalds
i like primo for the joints as well
never used deca but i'm assuming those who want joint benefits need not exceed 200mg EW