I am no expert, however from everything I have read and researched from all sorts of sources. Here goes.
Osta is a perfect compound for a cutting cycle, as it prevent muscle wasting. therefore you can be calorie deficit and lose fat and not muscle. Especially if training and diet are on point. (mine might not be as fluid as it should/could be) Like I said ive gotten bigger and stayed same weight while losing an inch on waist with no cardio. these last 4 weeks I will be doing cardio 3 days a week plus my normal lifting routine. Ill keep you posted.
S4 is supposedly the king of fat loss SARMS. but before you go and ingest 50mg READ THE DOSING PROCEDURE LAID OUT BY DYLAN G.
You start low and work up week be week and dose twice a day 12 hours apart. This SARM has the most potential for side effects and therefore tread lightly, and if you start getting symptoms either maintain and DO NOT increase dosage, or lower it, to where the sides subside. again do a search for S4 dosing procedures, I can share the link if you cant find it.
EDURANCE/CARDIO
GW is the SARM recommended for increase in endurance and cardio aid. It is what most users use when doing a gear cycle with lets say TREN because of the negative sides of TREN, GW combats those sides evening you out.
It really depends on your training/goals. I just got back into lifting after a hiatus due to new baby and other variables. So I wanted to get my foundation back while not gaining anymore crap weight. This is why I just did an Osta cycle. Next in line would be a full fledge cutting, and I will prob use all 3 SARMS S4, Osta, and GW and will be upping the cardio/circuit workouts to shed the excess baggage. Hope this helps.