well running that much Sustanon I'm sure the shorter esters built up rather quickly. anyways I usually don't recommend letro for the normal doses of test we usually see people running here just because of the fact that it is so powerful and can really crash your estro pretty hard and pretty quickly. and anybody that has done that knows recovery can be slow and the side effects really suck compared to having high levels. But considering how much actual test you are running you actually may benefit from using letro instead. assuming your gear is properly dosed, you are going to have serum levels through the roof and quite frankly would be pretty hard to crash your levels and like I said may actually find that letro will keep your levels more under control than adex considering the rebound effect if you use adex, I can imagine, is going to be quite large considering the amount that is actually being suppressed due to such high levels. this is just my opinion. I'm sure some people will disagree with this and others will agree. It's the way it works. But take it for what you will. I would just want nothing to do with a rebound effect that large. I personally switched over from adex to aromasin considering I knew I had really high serum levels. And did not want a rebound effect with serum levels that high because the rebound will be that much greater.my most recent blood test a couple of weeks ago showed my levels being over 10,000. so yes, I would recommend letro in your case over adex just like I chose aromasin over it in my case.