I actually agree with you on the interior not beeing at the same level as other highend cars such as the M5, or the Mercedes S Class. They have however spoken about an upgrade of the seats for the Model S, late this year, which might help it along. Here in Denmark gas cars are taxed 180% so a 85KW Model S is 610.000DKK and a BMW M5 is 1.600.000DKK. That makes the choice easy..