Years ago when I was in auto / retail service I saw the first E39 M5 and absolutely fell in lust until I had a chance to drive and work on many. While impressive overall, after driving one for a while you discover you really have to lean on it, wring it out to get the most out of it. If you're not thrashing it it does feel like a big somewhat under powered sedan (as a previous post accurately pointed out)
THEN I had a several opportunities to drive a E39 sport / 6-speed. THAT'S when I my lust shifted. MO
the best all around car for the money, when tuned, comes close to M5 overall performance but is sooooo much better as DD. It also comes with-out the BMW M-tax (that until you've shredded a large amount of $100 bills you can't appreciate their 'engineering')
When it came time to buy a really great example a few years back, I didn't even consider a M5 of that generation. I bought this..........................................
2000 Sport / 6-speed. Full BMW M5 body conversion, Complete HR suspension, ESS tuned with early large runner intake and resonator eliminator, Vintage Beyern 19"s, etc etc