I failed the depth perception test at MEPS and wasn't allowed to take it again. I ended up going to a civilian doctor and having a full eye exam and getting a letter written saying my eyes were sexy. It was stressful initially worrying about not making it medically, but in retrospect it wasn't a really big deal. Final select for SNA followed soon afterwards.
I talked to an old flight surgeon and he recommended keeping a bunch of copies of the letter with myself when I went in for my flight physical. He told me that if I ever had a problem with the depth perception test (probably will seeing as I have heard that the test is relatively uniform) to pull out the letter, state there was a complication but it has been adequately dealt with before.
He then told me to stop worrying because it did no good. That advice did me no good. If you have any questions, feel free to PM me.