The magic with the Volt is the AER of 40 plus miles, combined with 400 mile range (appx). For our family, almost 100% of our routine miles could be electric with a combination of a Volt and a LEAF, and we'd still be able to do the rare longer trips with the Volt. An alternate combination that could work would be two EVs and a rented ICE, with the rental possibly provided by the maker of one of the EVs through some program. Either way, scheduling that ICE would involve some hassle, and impromptu long trips would be problematic, perhaps. Of course, with the LEAF having CHAdeMO, it is becoming increasingly possible, if not as convenient, to use the LEAF for some of the intermediate distance trips.
That's the role that the PHEV would fill in my scenario. Right now, we're doing it with a LEAF and a Prius, but I'd rather have a Volt instead of the Prius.