E46 is fine overall. But...personally...I don't know about ones made in 2000. (That's just me.)
To put things into perspective, my coolant expansion tank cracked (previous owner used an OE equivilant, NOT OEM BMW). I was lucky to get away with replacing
JUST THAT one part but typically, you would have to replace everything, such as thermostat, hoses, radiator end tanks and all sorts of stuff. Then again, BMW has NEVER managed to figure out what they're doing wrong with their cooling systems since the beginning of time. Might as well go back to fucking air cooled motors.
On a Toyota/Honda/Nissan etc. If one thing breaks, just that one part breaks. Not an entire system or family of parts.
Bonus: If you ever browse BMW parts vendors, you will notice that many of them sell "maintenance packages." You don't see that with many Japanese cars.
