Worthwhile if only to get familiar with using the mic and recorder, to confirm proper settings on the recorder, and to become comfortable with your methods. Will you enjoy listening to the mono recordings? Give it a go, see what you think. Only you can answer that question.
Mono was the only option for recorded music for a long time! It can sound very compelling.
That said, I find making a good mono recording is harder than making a good stereo recording. It requires less gear and no stereo mic technique, but the constraints about being in the best position for making a good recording are tighter. Here's where I say something that is bound to be controversial, yet is true. The same applies to recording for multichannel surround playback. Its actually easier to make a great sounding surround recording than a great sounding stereo recording, but doing so requires still more gear and technique!