I have been doing some readings on these things and they seem pretty interesting. They claim to be very low to you None suppressive. They say they're the future of HRT. I am currently taking 50 mg of testosterone cypionate two times a week subcutaneously. I was thinking of adding S4 to this regiment for about six weeks at 25mgs twice a day.
I've done a bit of reading as well. Stopped after reading about vision issues, although that could be dose related and not an issues for HRT level doses. Being suppressive probably isn't a concern for HRT. You're should already be suppressed if you need HRT.
I think I will probably leave them alone until there's a lot more data. Just seems safer to replace exactly what's missing. Using and AI and HCG for decades might be a bit of a concern, but it seems like standard protocols are a bit more 'natural'.