Jaguar has improved over the years, however, still does not approach the cachet of Mercedes. If one compares price, performance, reliability, safety, and comfort at each model level, Mercedes always comes out on top.
In previous days, Jaguar made some truly great cars such as the XKE, however, those days have long passed and since then, Jaguar has struggled to produce viable compelling cars.
If you want proof, compare resale values on used models.