5N do have some reliability issue on AWB and AE especially indoor. AF, burst and data saving speed is also slightly slower than desired when compared to pro or semi pro DSLR, e.g. D700.
Having said that, I am asking too much for a 4k body, and I am a happy shooter w/ 5N + its kit-zoom and my small collection of legacy manual focus lens via 3rd party adaptors. I am eagerly waiting for its G branded high performance standard-wide zoom in its 2012 roadmap.