The price of the MMF-1 is rather steep, due to its current rarity in North America I guess (had to find one in Japan, and paid about as much after all), but this is not made of plastic like the newer models; technically though, they're exactly the same.
I must admit: the MMF-1 adapter looks nice on my E-P3, fits tightly, and works flawlessly with all Zuiko or other 4/3 lenses. Of course, CDAF slows down focus time of PDAF-based lenses while being very precise and remaining fast enough for either static or slow-moving subjects; AF is so much better than expected, actually!!!
Last but not least, the IQ of pictures stemming from such combinations (MFT bodies + HG FT lenses) truly rises above everything else that I've seen so far in Micro Land...
$300!? Well, having access to my priceless 12-60mm, 11-22mm, 8mm, 50mm Macro, and more on a mirrorless camera is... priceless.