The benefits of using Sustanon 250 during a cycle are the same as using any testosterone, plus a couple of extra added bonuses due to the ester mix. Sustanon can be used less often than other versions of testosterone while still reaping the main benefits. Benefits like increased muscle mass, increased strength, increased libido and improved recovery after each training session.

Since sustanon is composed of four different ester chains that release at different times, the user does not experience the same abrupt peak and sharp decline when compared to other esters. The consistency in levels of testosterone help to minimize the chances of estrogen spikes and severe HPTA (hypothalamic-pituitary-gonadal axis) suppression.




Rate for sustan of Testosterone Decanoate : Testosterone Isocaproate : Testosterone Phenylpropionate : Testosterone Propionate is 10:6:6:3

Testosterone Decanoate 100mg

This is one of the longest ester used in any steroid. It has a very long half-life, over 2 weeks (around 15 days), which means the active life of the ester is almost a month. In simple terms, from the time you inject decanoate, it takes roughly 30 days to leave your system. Though, you can expect the peak of this ester to be around 11-12 days not 15.
Interestingly, the decanoate ester is the main reason sustanon is considered a "once a month" drug. Users tend to think you can inject one injection of sustanon per month based on this ester alone. This is true for testosterone replacement therapy (TRT), but it's a complete fallacy for bodybuilding. Think of it this way, by the time you get to day 11-15 (~2 weeks in), you peaked and you used up most of the steroid. Therefore, you need another injection to keep blood levels steady.

Testosterone Isocaproate 60mg

This ester is a MID-range release ester, and it's used to bridge the gap between the release of propionate and the decanoate ester. Since it has a 9 day half-life, I never understood why it was used instead of cypionate or enanthate, which have a similar half-life. I suspect this has to do with price.
Knowing that sustanon was designed for testosterone replacement therapy (TRT), we can safely assume the margins on it are high. It's well known that Organon is making 500%+ margins on this steroid. As a result, using more expensive esters isn't necessary. Why change what works, right? If they add the more effective cypionate or enanthate esters, they'll end up shaving margins and losing money.

Testosterone Phenylpropionate 60mg

This is another MID-range ester used to keep testosterone levels steady as the propionate ester disappears from the system and the user waits for the decanoate ester to kick in. Though, some studies show testosterone phenylpropionate to have a 5.5 day half-life, it's widely believed the half-life is around 4.5 days. The same as propionate. Again, it's odd this ester is used when it has a half-life that's very similar to propionate.
I believe the phenylpropionate chain is used because base propionate has a shorter half-life than most scientists believe, and it varies from individual to individual. Meaning, different men process exogenous testosterone differently. As a result, the phenyl version of propionate is added as a safety net for steady testosterone levels.

Testosterone Propionate 30mg

The propionate ester is one of the shortest esters used in any steroid preparation, and it's one of the most popular versions of testosterone ever used. When used alone, testosterone propionate should be injected every other day (EOD). In the sustanon 250 formula, injections can be done weekly since the isocaproate and phenylpropionate ester are just starting their full release as the propionate ester wears out.
The reported half-life of propionate is around 4.5 days, but it's believed to be closer to 3 days by many bodybuilders. This might have something to do with the way the ester is cleaved off by different men with different health levels.
Basically, the propionate ester is the base of the sustanon formula. It's added as a TRT drug because it gives men with the usual TRT symptoms an immediate boost. Think of it this way, after years of low libido, depression and weight gain caused by low testosterone levels, you feel great within days of your first sustanon injection. Therefore, you can call the propionate addition to the sustanon TRT formula a psychological boost more than anything.