Mine replaced nothing except rental cars. I only live in the US about three months per year. However, I typically meant a BMW or MB from Sixt, so it does typically cost more than normal rentals. After renting a Model S I knew it would be a matter of time before I would buy one, so i did. My daily driver in brazil, where I live most of the time, is a BMW X1 (actually cost about the same as the P85D as a result of our horrendous import duties and car taxes). I have a nagging idea i might pull the plug on the X1 in favour of the i3, the only electric car currently sold here, even though the only version available has the 'range extender'. Probably I'll just wait until something better comes along, such as the Tesla Model 3.