R.B.
If you are concerned about him becoming "traumatized," then earlier is probably better. He will recall and understand more as he's older.
Get a second opinion, and maybe a third if you're still not convinced. One of mine had surgery for a hydrocele at under 1 year old. He wasn't traumatized at all, although it was a little scary for us. I was more trusting of doctors back then, and never questioned it or got a second opinion. If I had to face that choice now, I would research it thoroughly, and get a second/third opinion. But it all went well for my son.