I guess individual perception varies, to me Lexus LS series are the equivalent for merc/bmw both in terms of comfort and performance.

The same goes to Infinity Q50/60 series, they are just superb!

well.... those who go for luxury cars when looking at toyota and Nissan... they will always assume is for the mid to high executives... generally their highest range of cars doesnt even come close to the luxuriousness of Merc or BMW... however by using a more premium name... they can easily create a new luxury identity for them... and also target different market range so that the luxury buyers wont get confused...