I ran 500 mgs of test and 400 mgs of Eq and needed an AI but only needed to take it for about a week around midway through the cycle. Most guys will say to run an AI from the start at much higher than actually needed. Steroids are not good for you, but there are reports out there that say AI's are as bad if not worse in some ways the the gear. The AI's are absolutely worse for you that slightly elevated estrogen. My opinion is that AI's should be used in the event of side effects of estrogen, IE swollen hands, feet, ankles, itchy, swollen nipples, etc. Otherwise I just dont think that its worth taking them just in case. Also, what I have found, personally, the less you use, the less you need over time, and the less your body has estrogen related problems. This is just my milage, yours may vary.