[Amit3339]

We(team 3339) always used two drivers. There is no right or wrong with this question, I can say that I met a few teams that worked great with one driver and teams that liks us worked with only one and both had great results. The main point is that you should pick what is good for your team and stick with it.
As being the driver for the last three years I can say that the most crucial thing is the communication between the drivers(when you work with a pair). We usualy choose two people that have good communication(and of course are good at operating). After doing our selections we define the language between them so every element on the field and every robot operation will have a clear and short code name. After that.... it's just practice. I know it sounds easy when I say it but it's a proccess that takes time