And if they do what are they?

Yes. Mercedes-Benz used to make beautiful cars back in the olden days (30s through 90s). They were even better than cars like Rolls-Royce or Bentley. However, nowadays Mercedes is cutting corners. I'm not sure about the GL, but I know that the M class has tons of problems and breaks down A LOT, so the GL probably does too. If you're getting a used one, it should have many problems, however, the new ones are a little bit better, I think. You should ask a person who owns one.

The GL was designed to be the rich, rugged man's tool. It is not designed for women to be blunt. The steeing is significantly heavier compared to any other SUV of similar size eg. Q7. The GLK on the other hand was designed for women. Being an avid mercedes enthusiast and current owner of both an ML63 AMG and CLS63 AMG i hope that you will heed my advice. You will look severely out of place in that macho car.