I am a firm believer in having an electric pump with a float switch and a 3-way operational switch. I would encourage everyone to install a setup like that regardless of having a dry bilge.

I rarely get down to our boat during the week, should something leak (a thru hull or packing gland for example), my pump switch is always set to Automatic to handle it. In addition, at our club the members are encouraged to report boats that have bilge pumps that activate a lot. Absentee owners may not realize they have a leak for several days or weeks.