Pure summarize any problems encountered: it works like the B +, but much faster (we can finally play MKV big or even ISO Blu-Ray without slowdowns - no ISO 3D, but that's limiting XBMC / Kodi).
I've connected my key WiFi TP-Link: immediately recognized and configured without concern. All this, in my old box of Raspbeery B °.
So for a slightly higher price than the B + (especially in these times of "famine" / out), we have (finally) a real media center, capable of handling all video files (except ISO 3D ).
For audio, it's OK. anyway, it's not too hard that the problem but the software (XBMC is not terrible at this level, I find - especially in the management of the albums, covers etc ..)