yes there are MAJOR difference between the two thus they work way different. 6-oxo works by minimally reducing estogren and in a totally different way. atd causes estrogen to majorally go way down to the bottom of the barrell!
reference
Effects of eight weeks of an alleged aromatase inh...[J Int Soc Sports Nutr. 2007] - PubMed Result
as far as testosterone booth boosts testosterone as the Hypothalamus senses lower estrogen and raises tesosterone. 6-oxo works in a MAJOR different way and is way better imho.
of course one can do low dosed atd; however, most people dont know this and mess themselves up while using it high dosed.
Look at the rat study on castrated rats and 6-oxo which clearly shows it does not raise test and dht if a person doesnt have testicles. ATd may indeed though.
6-oxo works more in tune and naturally with the body than atd.