I'm at very early stage with Paddy - only 4 and a half months old, so not ready for an early or a late op yet!
This business of the dog being "mature" - is it only to do with behaviour or does it have physical side effects if it's done too early?
In all honesty, I haven't made my mind up. I often think - leave him entire, unless/until there are behaviours or issues which castration would (or would probably) solve. Other times, especially when one of my friends tells me about dogs being "fondled" by strangers in the park - to check if they're entire and worth nicking for breeding - I get determined to do it as a precaution. then I calm down and decide that's a dumb reason to do it....
I'd be really interested to hear from people who went ahead with the op as to when and why they did it, and whether it's panned out as they expected/hoped.
Denise