Been gelding colts for fifty years (not me, personally, you understand, a Vet!!) and, although I know this is tempting fate, I have yet to lose one. I have gelded colts and stallions of all ages and now prefer to geld at around 10-12 weeks old as it is the least risk/easiest recovery time, so best for the colt. Geldings, as I am sure we all now know, actually continue to grow longer than entires, but I have found the difference with Minis to be minimal (1/2 " would be unusual) so if you are not breeding against the limit it is not a problem.
I actually have met a number of human males who would benefit from castration, preferably at a young age so they cannot pass on their genes- but that is my personal opinion.........
I find geldings to be just slightly nicer versions of their entire brothers- DC was an insufferable colt and is still totally himself, but is just bearable, now (and I still love him).
The very fact that gelding, once the "art form" had become universally known, spread like wildfire, speaks for itself against those who would have you believe that a fieid full of stallions is easy to handle....actually, I do not beleive that anyone in their right mind, (outside of the Muslim world which precludes any sort of castration in spite of being one of the longest users of eunuchs) would actually think keeping a field full of stallions is easy or beneficial, and I speak as someone who keeps a field full of stallions (thorugh the winter and for a given value of "full"!!)