Each individual SARM has a different role, purpose and outcome.
MK-677 will help you add lean muscle mass and strength.
LGD-4033 will help you to increase lean muscle mass whilst dropping body fat.
Cardarine helps breakdown body fat, reduces training recovery times and increases lifting endurance. Great for fat loss and muscle building.
Ostarine is most commonly used to preserve muscle mass while in a caloric deficit. It's great for muscle building and fat loss.