My opinion is that at the effective dosages most are equal, though the effective dosage widely varies for some it does not, and that's where you note a difference. Rad 140 and lgd4033 are much stronger at 30mg daily than Ostarine at 30mg daily, but 50mg daily is where Osta actually shines whereas LGD and rad are effective at 20-30. I won't even bother with s4 personally, I can get visual side effects from AAS if I want those.
Yk11 is a bit of a different animal, it's methylated, and steroidal. 20mg daily would be a monster dose. And there are legit products with such a dose per tablet. You would be best stacking that one with mk677 and another steroid compound which results in massive and rapid growth such as DMZ or 1-Test.
Cardarine IMO is essential when using anything that makes your heart pound heavily, FYI. I would recommend that for any AAS or SARM cycle where blood pressure or cardio is an issue.