I shoot both B+W and color and IMO it completely depends on the subject matter. Some shots look much better in color and vice versa. I shoot more B+W because of the control I get in the development and darkroon stage but I often load up a second back with color transparency film and get some nice suprises when I put them on the light box.. Some feel that sticking to one or the other is a sign of focus but I feel as though I would be missing out if I didn't do both. As to which is harder? Its the one you're least familiar with.