Yes, suppression will happen and differently for many. It would be nice to take this time of logging to gather as much data as possible. Not just T number. Liver, cholesterol, etc... S4 has been seen to lower HDL. I didn't make my original statement with the intent of starting bro-wars. Just a mere suggestion for real numbers. The more numbers gathered the better we can deduce what effect these compounds have on homeostasis. If it turns out that a majority of RAD140 testers get shutdown (and how badly) then it will aid tremendously in structuring a proper PCT and/or preventative and supportive supplementation. This is basically new ground here. Most readily available info out there are paper claims or other than human studies.