Lots of mixed information.
BMW have a 6 year cycle on their cars before they phase in the new generation.
3 series
E46 started production in 1999 and lasted until 2005
E90 2006 to 2012 etc...
And every 3 years they have a series revision update or LCI.
On the E90 they also included a major change under the bonnet. The engine changed to the much newer N57 generation which is still used in the F30 bmw's.
The entire engine bay layout has changed, the block is no longer cast iron, more lightweight, more fuel efficient, more powerful, better heat dissapation New intake manifold, new intercooler design and location, new air filter design and location, new DDE DME LCM etc... The list is very long.
The drivetrain I'm not sure of.
Cosmetics have already been mentioned. Bonnet headlights, tail lights including LED design and suspension.
In short there is a huge price gap between them but understandably so.
Is it worth it?
In my opinion yes. The LCI is a much improved car over the pre-LCI.
Would I buy one?
No, because the M57 has lived a much longer life and has received many updates and is very tunable and also found very reliable over the years. And it's still a lot of car for very little money
Good luck in your hunt :thumbs: