First of all, it doesn't take multiple hours of downtime for charging. Generally stops at the Superchargers are only around 30-40 minutes. In the next few months it will only take 90 seconds when battery swapping is added. The Superchargers are also free and guaranteed to be free forever. Battery swapping will cost about the same as filling up a similar luxury car. Besides, usually it doesn't matter how long charging takes. I always wake up each morning to a full tank (or in my case usually 60% charge to help extend the battery life), so to speak. It takes me 5 seconds to plug in at night and 5 seconds to unplug in the morning. In a typical week I spend far less time waiting for my car to charge than I do waiting to fill up my gas car, which I've sold since I drive it so rarely now. In the cross country trip Tesla spent 80% of their time driving and 20% charging while driving through some fairly nasty weather. If you stop for the night, as most drivers do, then you wake up in the morning with a full tank. Tesla's sales have been anything but a flop. They can't make them fast enough. They're outselling the gasoline cars in their class by a fair amount and they're making a decent profit from each one sold (over 25% margins).
Add to that that there's not much that can keep up with it, gasoline or electric. Most electric cars aren't selling all that well because they have poor range, poor battery life, or are just plain ugly. They're econoboxes that can't go 100 miles. For example the battery in the Leaf is only warrantied for 5 years and people are seeing significant degradation after only two years in hot climates.
The model S does not have any of these compromises. The car handles beautifully and is very responsive with quality materials and it looks great, not like a frog, even though it has one of the lowest coefficients of drag of any car out there. It has tons of room since the battery is a flat skateboard under the car with an electric motor the size of a watermelon that delivers 445 ft/lbs of torque, 416HP with minimal transmission losses. The climate control works well as does the user interface which is extremely responsive (it's based on Qt and runs on Linux on a Tegra 3). Driving it is a blast, especially with 0-60 in 4.2 seconds (3.9 according to Car & Driver). While the range is typically around 240 miles of real-world driving that's not that different than many ICE cars I've driven. The response is instantaneous. There is no lag. There's very little maintenance required other than rotating the tires and replacing the cabin air filter and wiper blades. The brakes should last nearly forever due to regenerative braking. The one-pedal driving of the car is quite addictive. It lets you configure how it behaves as well, like if you want strong regeneration or not if you let off of the gas or if you want it to creep forward when you let off the brake.
The Superchargers are usually at locations where there's places to eat and stretch ones legs. On my last trip to Lake Tahoe I stopped in Folsom to charge. By the time I was done with my burger my car was charged and ready to go and there was plenty of range left when I got to my destination at 7200 feet near the summit of Kingsbury Grade.
In the next three months Tesla will have battery swapping between the Bay Area and LA. By the end of the year 80% of the country will be covered by charging. Already the West coast is pretty well covered as is much of the East coast. I can drive from San Diego to Vancouver without spending a dime on fuel and spend at least 75% of my time driving.
The car has a ton of space in it, far more than my Prius ever did. I have far more luggage space, not even counting the frunk, which I find quite useful.
Tesla's goal was to create the best car, not the best electric car. In many ways they succeeded. They've also done away with a lot of things that suck about buying a car like the dealerships and dealing with dealership service. Their warranty covers everything except the wheels and tires and I do mean everything. Brake pads, wiper blades and other consumables are covered. Their goal is to not make a profit on service. They'll even come to you no matter where you are in the country for $100. If you like your loaner car, which is typically a high-end P85, you can keep it and pay the difference in value. They're actually having a problem keeping enough loaner cars in stock. The last time I needed service they were out so they dropped me off at work and delivered my car to where I work when they were done (or they would have provided a rental on their dime).
On top of that it's one of the safest cars. Nobody has had a serious injury in a Model S despite a number of bad accidents. It broke the machine doing the crush test and they could not make the car flip without going to extraordinary lengths. In the side pole test it outperformed a Volvo by a significant margin with far less passenger intrusion.
They also regularly add new features and capabilities with over the air software updates. Some of these were a surprise. For example, they announced battery swapping after I bought my car. None of us were aware that this was possible with our existing cars but it is. Others like having the Google maps automatically rotate were not in the original software, and they are fairly quick about addressing bugs in the software. For example, when I first got my car if I had the wipers on when I got into the car they would start up immediately before the drivers door was closed, resulting in getting wet. The next update fixed that. Or when that fire happened in a house whose wiring was not up to code within two days Tesla pushed out an over-the-air software update to detect substandard wiring and automatically reduce the current draw to prevent future occurrences, presumably by using the data logged by the car. Any other car would have taken weeks to months to get a software update and you would have to bring it to the dealership to get it fixed.
When you consider that this is their first car built in their own factory with almost nothing in common with their Roadster it is pretty amazing. The worst thing I have had with my car in the year I've owned it was some rattles which Tesla addressed on my car and already rolled the fixes into their production line.
Notice I haven't said anything about being green. I know plenty of owners who are fairly conservative, it's not a liberal vs conservative thing.