just wanted to say, my young Birman cat was neutered
at 8 weeks of age. He had no problems at all, and has yet
to develop any nasty male cat habits...like spraying!
Hopefully he wont...hes about a year and a half now.
I know many many vets are opting to spay/neuter now
between 8-16 weeks of age.
I think you would be fine to get your guy neutered now.