How old is he? About a year, right?
i just went through making this decision. For me there were pros and cons and the pros outweighed the cons. for one thing, Zack, age 7 months, was developing new peeing behavior that i hoped neutering would curb (peeing where not supposed to). Also, i'm working on training him and have read that training is easier for the dog to concentrate if neutered. And also most important his ability to impregnate was undesirable. I didn't believe i could prevent him from getting another dog pregnant and i didn't want to take the chance that he would. Also there are supposed to be some health benefits. For one thing, they won't ever get testicular cancer. :?
On the negative side of neutering, for one thing, it just goes against my grain to have my little guy cut on. And i know that when women i've known have had early menopause caused by having their ovaries removed, they have had health problems caused by that, and are at a greater risk of osteoporosis. I felt that whatever risks there are to a male puppy in being neutered are probably not well studied or well known so that i was taking a risk. but millions of dogs get neutered and live to a healthy old age so i ended up deciding to do it. It was quite simple, not hard on him except while he was still under the effects of the pain shot she gave him, he was very out of it and did not seem to feel well at all, not the faintest wag of the tip of the tail, nor a little lick of greeting, he was groaning. But by that night, he seemed happy and i'm so glad it's over.
i learned that there is a really wide price range for neutering and if i could do it over again, i'd ask more questions about the price and choose someone experienced and cheap.