First off let me answer some of your questions. I have been researching silicone male genital modifications for years. All guys that get silicone do not look freaky, discolored, and oddly shaped. Most of the discoloration and uneveness is not caused by silicone but by extreme pumping and/or saline infusions done before and after the injections. Silicone is associated with the huge freaky looking dicks because it is so obviously injected or enlarged with something. But pornstars, body builders, and models have been getting various body parts enlarged with silicone since the 70's. The procedure now is much more safe and the results far better with better quality silicone and improved techniques.
Silicone is an inert material. It is not toxic to tissue and cells. Silicone only causes problem when it enters organs or the blood stream. When women's breast implants leaked, the silicone was near to the lungs and heart. When silicone enters the lungs it can cause problems with breathing. When silicone enters the heart it can lead to heart attacks or enter the blood and cause health issues. As long as silicone does not enter your blood stream or organs it is completely safe and will not compromise tissue or cells. Also silicone loose in the body becomes surrounded by collagen which adheres it to others tissues. Over time blood vessels form around it making it basically a part of your body. So when women wished to have the silicone removed it was only possible with extensive surgery that often caused some the surrounding tissue to be removed. In male genital modification, the fact that silicone becomes permanent and adheres to tissue is wanted. This is what causes the enlargement and keeps the silicone in place. Because of the location, you don't run the same risk of silicone entering your blood or migrating to your lungs. The only way that large amounts of silicone can make their way to your heart or lungs is if an unqualified person injects the silicone and hits a vein. But a licensed doctor familiar with silicone injections knows how to avoid this.
When silicone is injected correctly by a medical professional, the result can be astounding. Most of the abnormal siliconed genitals that you see are done by a practitioner overseas who is not licensed. There is also a couple of guys in the US who do it as well, but as far as I know they are not doctors or cosmetic surgeons either. To get the best results, you must go to a medical doctor or cosmetic surgeon familiar with the procedure who uses only pure medical grade silicone. Any lesser grade silicone can result in a bad finished product which can form lumps over time. There is only one qualified practitioner that I know of and he has a private practice just outside of San Diego. He has worked on other pornstars and I believe some guys interested in weightlifting and modeling.
So keep in mind that all silicone dicks do not look like Bulge Marc's. I am not saying anything bad about him because some like that look. The size to me is hot. It looks amazing in bulges. The discoloration and shape when it is showed take away a little from the size for me. Obviously he is happy so I am happy for him. But a dick with small amounts of silicone can look pretty natural. Those that get small amounts are hard to pick out and they don't often tell people that they have silicone because they want people to think it's natural.
Bulge Marc also had multiple rounds of injection for years. The more silicone you get in your dick the less like a dick it will look. Guys that get one to two rounds can maintain a mostly natural shape and their penis still functions as normal. Large amounts of silicone can prevent easy penetration. Just imagine a stick surrounded by a really fat marshmallow. The dick still gets hard inside of the silicone but the surrounding girth often causes issues. Large amounts of silicone work better in the ballsac than in the dick.
Below is a link to a video of Remi Nunes. He is a guy who has been sensibly siliconed.
Remi Nunes Outdoors