There are quite a few 4/3 lenses available used. Are there any that are worth getting, e.g., that are good bang for the buck? I have heard autofocus is slow etc. On the other hand, there is some fast glass out there - I saw a Rokinon 85mm f1.4 in 4/3 selling for $179, which looked intriguing. Any info on adapting 4/3 to mu 4/3 appreciated.