More pricey than Apex but OZ Ultra's are light/strong and frequently pop up on forums (zpost, e90post and e46fanatics). I'd look out for a set from there. The Alleggerita's are also pretty good and on sale at TR at $339 each for 18x8 (fewer than 3 left so hopefully they have a pair left!)
http://www.tirerack.com/wheels/Wheel...7&autoModClar=