I think a lot of this depends on the individual. My natural preference is to use the touch screen. It's not about what's "better" in absolute terms, but what re

I think a lot of this depends on the individual. My natural preference is to use the touch screen. It's not about what's "better" in absolute terms, but what requires the least amount of thought/brain power for the person (my guess is that time is a major factor of the cost calculation - it's quicker to do what is natural). The cost of hand motions isn't significant by comparison.