went out to test drive some cars today with my mom?

We went test driving today and she liked 4 cars that we test drove. her budget was around $50,000 and all these cars were around that price range. She pretty much only has owned land rovers and range rovers and wants a car for her daily driver. These are the cars that we absolutely fell in love with and can't decide which one to pick GM Scan tool. Here are the vehicles.

2010 audi s5

2007 bmw m6

2008 bmw m5

2010 lexus IS F

What one would be the best daily driver and which one is the most reliable? My mom is really sick and tired of having to fix her land rover.