Sustanon is the only ester I will never use. Short esters are fast acting but require more pining. They also clear fast so your can start pct soon.
Slow esters reduce pinning and provide more stable level.
Sustanon is the worst of both worlds. Not enough is fast acting to do a short cycle, and it will not clear fast due to the long esters being in there. And due to there being so many different length esters in there your blood level will go up and down as different esters wear off and kick in unless you pin really frequently which would defeat the whole purpose of a long ester in the 1st place. Sustanon was a failed attempt to make a test that you could pin less often than test C for TRT. It failed miserably at that even TRT clinics don't give it.