The E39 is a pretty amazing car, definitely the best 5 series BMW has made. EVERY surface on the interior is soft touch, covered in leather etc. I have 18 way power seats in mine from a 750iL, 6 speed, tons of torque, nice V8 sound etc. But the car seems almost engineered to be impossible to work on, and the smallest jobs are 4-8 hour ordeals with hundreds of dollars of parts, and brittle plastic ones that you break along the way just touching them.
Amazingly fun car, but it grows old owning one after a couple of years.