I would have weighed in sooner, but I just saw this topic. I grew up in the military, and I will say that yes, it did take care of me and my family at a price. My father was a recruiter, mp and later headed a bio med unit at a military hospital. When he was a recruiter, he used to actively discourage "gender variant" (quotation used to imply anyone who did not fit the typical male/female roles) people from joining because in his words - "it's not safe, especially if you end up in the wrong basic group." He told me that I was, under no circumstance to join because I was too masculine for a woman and he had watched young women (mostly who were percieved as lesbians, whether or not they were didn't matter) get harrassed and a few who were assaulted. As per standard in the military, sexual assault rarely leads to prosecution.
I would consider all potiential outcomes before you join the military. If you fel the need to perform a service similar, why not look into law enforcement, fireman, or something similar? The military is a situation where they don't care about equality because you sign your life over to them for a set period of time. Even with DADT repealed, my dad's friend has dealt with a huge amount of emotional hell from his fellow airmen and soldiers. Make a list of what you want to get out of it, and see if you can find a different job that would offer you the same things.
If you want to join, detransition to join, or anything inbetween, it it ultimately your choice. However, I would take all avenues into consideration. Even if you decide to get yourself kicked out later because you don't like, discharge from the military will follow you like the plague.