Testosterone is the prime male androgen in the body, and as such still the best possible mass builder in the world. It has a high risk of side-effects because it readily converts to a more androgenic form (DHT) in androgen responsive tissues and forms estrogen quite easily. But these characteristics also provide it with its extreme anabolic tendencies. On the one hand estrogen increases growth hormone output, glucose utilization, improves immunity and upgrades the androgen receptor, while on the other hand a testosterone/DHT combination is extremely potent at activating the androgen receptor and eliciting major strength and size gains. While not always the most visually appealing result, there is no steroid on earth that packs on mass like testosterone does.
Sustanon 250 is a unique blend of 4 different esters of testosterone. The principle purpose of attaching an ester to a steroid is to make it more lipophillic, so that when injected intra-muscularly it can remain in the adipose tissue longer and is released in the blood-stream over time. The longer an ester, the more lipophillic it is. Sustanon 250 contain 1 short, 1 long and 2 medium length esters that are all delivered over time, which gives a quick release, but a durable one as well. You may think that this is a positive thing, and to patients requiring testosterone therapy this probably is, but to a steroid user its really not.
A steroid user will use a long-acting testosterone and inject it once a week. The end of a week is usually the time when a long-acting (7 or 8 carbon) ester has tapered down to its original level and threatens to drop below that level, giving sub-par amounts of testosterone beyond that point (eventhough the compound stays somewhat active for 3-4 weeks). With sustanon, that equal amount is divided much differently. Imagine a hypothetical situation where one take either 270 mg of a an ester that lasts 6 days, or 270 mg of a blend of different esters, 90 mg each, that release over respectively 2, 4 and 6 days, analog to sustanon. With the first one, an even amount of testosterone is released on each day. With the second one the entire first ester, half the second ester and 1/3rd of the last ester is released within the first two days. The result here is clear : the first two days one gets 165 mg, the next two one gets 75 mg and the last 2 days one gets a mere 30 mg. The levels peak much sooner, and drop off sooner, leaving you with less than adequate androgen levels as the week draws to a close.
So for use as one would use another long-acting testosterone, I find sustanon to be poor value. The price is roughly the same so I really don't see the affinity people seem to have for it. Respectively cypionate and enanthate are much better choices. I can understand the need for a fast-acting component to front-load and kick-start gains, but even then, testoviron (200 mg testosterone enanthate and 50 mg testosterone propionate) is a much better choice. Speaking of front-loading, for this express purpose sustanon may be very suited. One could probably obtain results faster If one were to use 500 mg of sustanon on day 1, then again 5 days later on day 6 and start a cycle of enanthate/cypionate at 500 mg/week on day 11. That avoids the major crash at the end of the week and makes maximum use of the fast acting esters to saturate the system.
As with all testosterones the rate of side-effects is quite high. Risks of androgenic side-effects (hair loss, prostate hypertrophy, deepening of voice) as well as estrogenic side-effects (gyno, water retention, fat gain) are real, and the use of ancillary drugs such as anti-estrogens will most likely be needed. This is something that I urge all users to take into account. Never start any cycle with testosterone without having at least a lot of Nolvadex and a few amps of HCG on hand. Testosterone is not in any way toxic, and should not give a user any problems apart from a high rate of occurrence of standard steroid side-effects.
Because of its long-acting components, sustanon is mostly used as a form of long-acting testosterone. Much like testoviron, testosterone enanthate and testosterone cypionate. I don't find it to be the best choice for this purpose, but obviously I don't determine the trends among bodybuilders. In such use doses of 500 to 1000 mg per week are used in a single injection, with decent results nonetheless. Perhaps because 3 of its esters are notably shorter than enanthate or cypionate, so more of it is actual testosterone and less ester, eventhough the distribution is uneven. Its best use in my opinion is to start off a cycle with, by injecting twice with 5 days space, and then give it another 5 days before starting an 8-10 week cycle of testoviron, enanthate or cypionate. This should allow for more testosterone to build up and results to come much faster.
Again, because of the two medium-length and the long ester, the compound is not very controllable. So when problems occur, simply discontinuing the product is not an option. One needs to be familiar with anti-estrogenic compounds for one. When signs of gyno appear using 20-40 mg/day of the estrogen antagonist Nolvadex or 100-150 mg/day of its weaker counterpart clomid until a few days after symptoms disappear is advised. The best way to avoid such problems is running proviron or arimidex, aromatase blockers, alongside the product. In most instances I give preference to arimidex, but when concerning the use of testosterone Proviron at 50-100 mg per day may be wiser since it frees up more testosterone.
Of course the simultaneous use of an aromatase blocker will compromise your gains since it literally stops estrogen from being made. Androgenic problems can be reduced to some extent by the use of finasteride, which will stop the conversion of testosterone to its more androgenic component DHT. This may alleviate aggravated hair loss and prostate problems somewhat. Again, the blocking of such a conversion may decrease the gains made and will in any case heighten the risk for estrogenic side-effects, since DHT acts as an anti-estrogen. Proviron is also a form of DHT, so people worried about androgenic side-effects should then naturally opt for arimidex over proviron when they choose an aromatase blocker as well.
Sustanon stacks well with any compound. Usually testosterone is always the stronger compound in the stack, so whenever you stack something alongside its usually because the drug has certain characteristics. Usually this means it will be a milder drug that will allow the user a milder cycle with lower occurrence of side-effects than simply using more testosterone, without having to give up all of the potential gains. Deca-Durabolin, Equipoise and Primobolan are some of the more fitting compounds for this purpose. But naturally the king of all mass-builders stacks well with almost anything.