NFS 4 was the last one I thoroughly enjoyed. Porsche Unleashed was nice too but way different. But the series from NFSII-SE to PU was what I played with friends from elementary school after we got home so it's a key memory for me and I might be biased.
Gaming back then was just different. The games from that era are the only ones I regularly come back to even after it's been almost 30 years.
GOAT
it's that one game I have on each device I own and carry around alongside AD1503