Most of the sides you will get from tren are basically estrogen related I.e prolactin issues will arise if estrogen is not kept in range so that why people like low test as there is less to convert.if this is your first tren run I'd say run tren A as you can quickly gauge how you react to it...plus if it's too much you can adjust or drop and its in and out...Obviously there are other sides but starting low n work up you can gauge yourself...good luck