This is just me but I never use an AI, mostly because I never go high on test. I don't like the idea of too many compounds in the body each causing their batch of side effects. I believe the ratio between test/estrogen is more important then specific levels but there comes a point where estrogen becomes too high and you need AI. There for I never go above 125mg EOD of test (437.5mg/week). I don't stay there for long either (4-6 weeks).
AI has it's place in controlling estrogen depending on dose and length on.
I don't need anything for estrogen control up to 400mg Test/week. If I go 600 or 750/week, I will use 5mg Nolvadex ED and that keeps estrogen in check for me (30-40 range). For me personally, AI are just overkill and not needed in my case. If you were to need an AI, I would recommend Aromasin as it's a little easier on the lipids.
i use 500mgs/week test E, tried using an AI once and my wrists started killing me along with my elbows, not sure if it dried me out to much or what..it was aromasin @ 12 mgs day.. i scraped that after i went to the orthopedic and got cortizone shots.. I dnt feel i need an AI on just test E.. but im kinda thin anyways, and stay lean.
It's all individual, some guys will need one on 500mg a week, and some guys don't need anything running grams of test.
For me personally when I first started I was very sensitive to estrogen so I needed one even on very light cycles..even needed letro to get rid of bad gyno that was developing. As time has gone by I can get away with far less anti e's and sometimes don't even need one running fairly high doses unless I'm dieting. Acne was terrible at the start too and now pretty much non existent other than a couple randomly here and there. I'm not sure if anyone else has experienced their body adjusting like this over time.
When I first started using testosterone I used an AI but haven't used any for the past few years and feel a lot better and have no side effects. I never go over 500mg of test though and if running multiple compound I keep them at 300mg.
I used to be able to run anything with no AI's or SERMS. Now as I've gotten older I cant even run TRT dosages without having to run something. I've never felt it hindered my gains much and often feel like I look much better when using an AI.