I'd check this article by Roger Cicala, talking about image degradation when using adapters, just google it:
"There Is No Free Lunch, Episode 763: Lens Adapters"
Short story is that no adapter (and he tested branded, expensive ones) would be exempt from a massive degradation of image quality, mainly because of slight misalignments which are inevitable when using it.
Maybe that won't mean much in real world usage, but it's another thing to be aware of.
A couple of years ago I was considering a NEX in order to have focus peaking in a small body (even though the adapter somewhat nullified the gain), but decided against it (awkward menu structure, it was a Sony - "the" brand of lost causes and failed standards -, and this adapter issue), and bought a K-01...
Last edited by LensBeginner; 10-20-2014 at 11:14 AM.