No argument there, I used 'em for years when I was heavy into mountain biking. I had a wicked Shimano set. But there's quite a bit of speed and weight involved with a minibike. I wouldn't, anyway.
i will mention that i find v brakes work very well on bicycles when adjusted perfectly, if they aren't perfect they cant do crap! i don't like the front brakes only idea, at all, you can slam on the bakes and crash, or not slam on the brakes and crash. you can buy a complete made in japan drum brake setup from bmi for 15 bucks......