I had my girl done just recently because she was limping on a back leg one day and I was worried.( My first GSD had the same symptom one day, took her in at just under a year and she was severely dysplastic and up until that day had not shown one sign of HD.)
Holly's xrays were gorgeous and I no longer will worry about her hips. She will be 3 in October. She is spayed, so I didn't do it for breeding purposes, which of course anyone who is planning to breed their dog, male or female, should certainly do.
Peace of mind is nice to have, so xrays are done for that reason.
Your puppy is young, usually they are not done that early unless you are seeing issues/concerns. I have xrayed as early as three months and seen horrible hips, but the puppy was showing signs and in pain. I would probably wait until 5 or 6 months, but the choice is yours.
Peace of mind means a lot.