I had a tear repaired at 9 weeks postpartum after ds2 (had a 2nd degree tear that I left unstitched and it healed totally open in a V). It was a super quick surgery, in and out in 45 minutes, but I was put under for it. My GYN encouraged me to do the surgery ASAP to help everything heal back up as normally as possible.
The actual healing was really hard. I assumed, b/c it was outpatient, that I'd be able to go back home (3 hours away) the next day. But it hurt to sit too badly and I ended up staying with my grandmother for about a week.
Sexually, things took a bit to get back to normal. By about 3 months post surgery I felt normal again. I was glad that I got it repaired in the end, even though recovery sucked.
And, just in case, I just had another baby and everything held up just fine. My MW worked really hard to make sure I didn't retear along the scar line.