When you look at what the Volt can do compared to the EV-1 or any other electric only car I'd say it does a darn good job.
Here's a challenge for those 75, 100, or 200 mile electric cars. Start out on a trip from the Pacific Ocean to the Atlantic alongside a Volt. Then tell me which ones make it to their destination quickest, without any support vehicle tagging along to recharge them.
With the volt, when the battery goes dead the engine starts and keeps the vehicle going. Performance is not noticeably different. Enough power is replaced in the main battery while the engine is running to handle limited low speed operation, provide for smooth starts from a stop, and enhance overall efficiency by using power from regenerative braking.
I assure you that on a trip like I suggest the Volt driver will be happily driving along while the others will be plotting their stops at charging stations. The Volt owner can even plug his car in at his motel while grabbing 40 winks and not care if he leaves the next morning with a full charge or not.
Oh yes, when it's cold as a well diggers south end, that little "Range Extender" engine will kick on and provide some heat. On an electric only vehicle the battery will heat you too but at the expense of mileage. (unless you put one of those propane heaters in the back seat).