Can you compare your 540i (e39) to your 550i (e60) for me? What did you really like, what didn't you like. They are both cars that still feel analogue, and I could definitely see myself picking up one in the future as a DD.
Current: 2008 BMW M3 Sparkling Graphite/Bamboo Beige/6MT. 1999 BMW M3 Techno Violet/Dove/5MT. Next: 2017 BMW M3 Austin Yellow/Cloth/6MT