Do some homework. I can tell you that at 1mg ED you won't have a problem with estrogen as your aromatase enzyme will be 86ed but so will your lipid profile if you use high amounts long enough. Aromasin is the way to go.
I think anti-e's are used wayyyyyyy too much. First off, most except aromasin will destroy your lipid profile. Also, if your trying to gain muscle, estrogen is very important and with too little, you will not gain size. The best way is to get a bloodtest at www.directlabs.com Lets say your on 800mg test and 500mg deca and your using .5mg adex ED get an estradial test done. If your estro comes back too high, then maybe bump it to .75-1mg depending on your reading or if its too low, then drop the dose to EOD. Its only like $50 to get it done and it will probably contribute to %30 more gains if you know how to map out your estro.