I may not remember exactly correctly, but I thought my doc said that an MRI would be unlikely to detect a sports hernia, but would pick up an inguinal hernia. In fact the best test for sports hernia is a very special piece of finger insertion that you will remember for the rest of your life, taking a path into your body that no man should ever discover. In the words of Jim 'Wash Out' Pfaffenbach from Hot Shots! - "ain't no man taking that route with me"!!
If its inguinal, and it looks like it might descend, you have to ask yourself whether you are willing to wait until it appears as a squatter in your scrotum. I had mine both whipped out.
My recovery from laparoscopic repair of bilateral inguinal hernia was probably not typical. I did a race about 3-4 weeks after and ran within 30 secs of my 5k PB. But the swim was "interesting" with all that tightness in my abdomen. It was probably a really shit idea. I think most people are out of the game for a fair bit longer than that.
The most fun part is post surgery, if they do lap repair. They filled my abdomen with CO2 and inflated me. After the op when they had sewn me back up again, I had an intense and painful feeling that I needed to fart out of my armpit.
I feel certain that this has all been no help to you, but I enjoyed remembering it.
EDIT: apologies, I read your title as Sports Hernia/Inguinal Hernia when clearly that isn't what you meant. Should have paid more attention. the bit about the SH test still stands though, you need to find somebody willing to poke you.