Have not feel a real difference between intra muscular or subcutane injection.
The T levels and also the E2 production seems to be the same.
If you are using the correct stuff, subcutane injection is really healthier then musculat, because, what you feel under the skin is the same thing what it does in your muscles. Only you can't feel it in the muscles.
The most products are too thick for good result of subbcutane injection. You need a thinner oily base and the only one product what I have found here is "Testosteron Depo" from Galenica. It's good available in eastern europe. But what is good anywhere else around the world... don't know!?
It sounds funny, but I only inject it into the ballsack, because there is very soft skin and there it has never build any bubbles or so.
The result is the same as every other skin region. If you have a round belly, there also is a really good place!