Shan2nu, though you may not agree, you tend to put too much focus on performance. A car is not all about 0-100

A car is much much more than that, like safety, comfort, ride etc. etc.
Merc is a trend-setter, they were the best car makers and arguably still are (barring recent quality issues). It is not for nothing that they charge such a high premium for their cars (and still manage to sell their cars).