Not really a scientific comparison but just got the 9-18mm and my dad has the Tokina. - on E-PL2 and T1i side by side - Tokina @ 11mm - Oly @ 9mm - Sample of Oly As you can see, in terms of horizontal angle of view, the Tokina is very slightly wider since it is equivalent to 17.6mm (with a Canon crop factor of 1.6x); that's only 0.4mm wider! It would've been wider on other mounts, like Nikon and Sony. Vertically, however, the Oly is even a bit wider (or taller) because of the 4/3 aspect ratio. Then there's the size and weight difference where the Oly 9-18mm is just obsurdly puny for something that covers 18-36 equiv. However, the Tokina is fast at constant f/2.8 and is very robust as the barrel is metal. Also, you can slide the focus ring forward to enable MF and back to enable AF - nice! Tokina is really good especially for the price and makes the 700USD retail price of the 9-18mm seem like a rip-off in comparison. Fortunately, I got the Oly for a good price locally (from Bestbuy of all places because it was an 'open item' but looks new and is complete). The 9-18mm is my second favorite lens right now (after the 20/1.7). Do I even want/need the 12/2.0 anymore?