Use dermacrine as a test base to keep your energy up.
None of them have very many androgenic side effects that effect your outward appearance like AAS. So acne, balding, oily skin, etc. is unlikely with sarms, but not impossible.
On the inside, they mostly have the same effect but to a lesser degree. Slight liver toxicity, an effect on cholesterol, testosterone suppression are all side effects sarms.
S23 or LGD seem to be the most powerful.