I just registered to this forum to find out if anybody has long-term experience with the Tesla Roadster. Personally I never encountered any electrical device with Li-I batteries that kept its quality for more than a few years. All my laptops worked for 3 hours at the beginning and (now at age 3 to 4 years) only for about 1 hour , my robotic vacuum cleaner could go for 40min before recharging and now (after 3 years) only 20 min. I suppose that someone who can afford a Roadster can also afford new batteries (worth 60k USD) after 4 years. Model S owners will probalby have a problem with paying another -say 30k USD after 4 years. What do you think?