Being one of the 3 BMW owners who love their e60 cars, have you considered these? I owned a 540i for 2 years and then moved to my 2008 550i. I found the 540 was a fine car but it wasn't aging well for me. To some the simple styling of it just looked dated. In M5 form it was better. The wagon is an aquired taste but I think the e60 version is much sportier. The interior looks to be holding up quite well also.