You are going to laugh, but our 2000 M5 has 9000 miles on it It's been a great car, no problems. Folks are right though, parts for the M5 are going to get very spendy as time goes on. However, what a driving experience....a few notes:

Josh is right, '01+ models came with the angel eye headlights, new steering wheel, and gray faced gauges. '00s came with old headlights, older steering wheel, and black faced gauges. Navigation screen did change in 2001 as well.

I think in '01 they changed the weight of the oil -- not sure on this one. The '00 calls for 10w-60, and despite it being $7-$8 a quart (YIKES), its worth it.

There are two styles of interior. The 'Sportive' and the 'Exclusive'. The Sportive has the two toned seats (if ordered with such), and aluminum trim. Very nice. The Exclusive has the one color seats in a different stitching, wood trim, and leather on the dash, door panels, and center console. It's very very nice. In 2000 you could order the 'extra' leather with the Sportive interior, but they nixed that for 2001 (we got it and the extra leather is very nice -- it's a $6000 option over in Europe, and with the new M5 they are now making it a pricey option).

So with all that said, I really wouldn't worry about years too much, I would focus more on condition and mileage. All the little bits that were upgraded can pretty much be done on a 2000, but certainly have a BMW dealer check ANY used M5 for (pay them an hour or two of labor and have them check it head to toe) and go from there...you will LOVE the car though.

Are you prepared for a manual tranny in DC traffic?