Back in the old days we used to run S4 at 75 mg a day and no one said a thing. Now people are scared to even run 50 mg a day. I just don't understand it.
Definitely pick n2guard. Many ingredients in the formula to help your kidneys, heart, and liver, and it also has ingredients to help everything and make your hormones work better too.
A safe SARM stack for someone your age is some simple GW and Ostarine. There's no reason to complicate things. You should also make sure that you get your blood work done.