Our hybrid will go about 100 feet on battery.  A PHEV will go 35 miles or so.  I'd be interested, I think, in a PHEV with maybe 10 miles of range, lower weight, lower cost, easy to charge with 110v.  I don't know that ~35 is optimal for everyone.  Our 100 feet is not enough to be notable really, but it gets good mpgs around town, not so great on the highway.