Sudah nongol tuh disini :

http://www.slrgear.com/reviews/showproduct.php/product/1137/cat/15

kesimpulannya :

If you're in the market for this lens, you're probably looking for some words of encouragement before you take the hit on your credit card: allow me to offer some. If you need this lens for professional purposes it will deliver unquestionably. If you want this lens because your standards are very high, they will be met. Olympus has clearly invested a lot of time and energy into producing this lens: the results speak for themselves.