I used the traditional chuck and bur tools, Star 430K push chuck,Kavo button and the Viper (high torque) button.
My personal preference is 430K and Viper, slightly inclined to 430K, because I find that it requires less maintenance compared with other hand pieces. I know that many dentists, especially in New York, use Kavo, and Kavo seems to have been used as a benchmark by dentists, at least in the northeast. Dental reps pointed out that Kavo's torque is the fastest and most stable, but I don't think it's true. In fact, if you want a quick cutting bit, I would say that the viper cuts the fastest.
Star 430K is not cutting the fastest, but it is my most reliable hand and requires minimal repair. It was a compromise, but my star 430K was my practice horse and it was good for me.
