Very good choice!
Keep the Honda for everyday-use, it's a shame to use the M5 in everyday conditions. it's a fun car and perhaps the quickest limo with sports-car qualities.
Also for the people looking for a M5. Check the produktiondate! Car till 03/01 used to consume too much engine oil. Many of them had engine failures and had a new engine or a new motorblock("small block")
At 03-04/01 there was a motorrevision. The new ones had new cylinders, new motorblock and new Oils were used. Castol TWS 10W40
The prices in germany for a 2001 modell with 30-50tkm are about 35-50k€