Honestly, it has been changing a lot. At first it was the 35/1.4 ASPH, then the 28/2, but now I am using the 50/1.4 ASPH a lot. I still have not quite sorted this camera out. I like the field of view of the 28, the depth of field and speed of the 35 and the performance of the 50...Part of the problem is that my M8 is broken...the 6 bit code reader does not work so using the 28 means cyan vignetting. I will get it fixed when I am back in the US...