I'm not sure but judging body, feathering, size and sex characteristic development, I'd say BUD is around 3 mo. old, if that. He's very tall for his age but he is really just a big chick. I know he may be on the big size for this kind of thing and I may not attempt it, but I was handling him today and he has very little feathering in that space and I was thinking, "Hmmmmm....wonder if I could yank his hoo-hoos and change his meat production, not to mention his attitude....."
Poor BUD...he's probably thinking, "What did I do to deserve this lovely~ but sometimes suddenly painful~ hell into which I have been dropped?".
Yes, it would improve meat quality. But keep in mind as far as caponizing, that the best time to do it is 4-6 weeks(the Chinese perform it at 3 weeks) because the testicles are smaller, with less connective tissue so they are easier to remove, and with less blood supply there is reduced risk of bleeding. That being said, if he is an immature 3 month old, I think it would be easier than if he had more sexual development. That has been my experience, albeit limited.
There is some increased risk of getting a slip with the older birds, but if you get most of the testicles, you will see a lightening of his comb along with a reduction in its size, along with a more docile attitude. As the testicle begins to regenerate, which will vary according to amount of testicle left behind, you will gradually see the secondary sex characteristics return, and quite often, they will begin crowing. It still gives him additional time to grow and get more meat on his bones, though, so there would be a better quality of meat than he would have been at the same age had he remained intact. If he is 6-7 months of age when that happens, then he will have more meat on his bones than if he were 4-5 months old.
So, worst case scenario, you have a slip, but he is heavier (because he is older) at the time of slaughter and has equal or better meat quality than if he had been left intact. Plus you get experience with caponizing. I caponized a couple of 16 weekers earlier this week, but they were immature, so things went pretty well. It seems their combs and wattles have already lost some of their color.
Just remember if you decide to caponize BUD, get the testicles and all of the vas deferens and surrounding connective tissue that you can....even peritoneum around the testicle that you can pull loose and remove. You don't want to leave even a smidge of testicular tissue if you can help it.