some short info:
i get yesterday my "ODROID C2" Device ( because of lack of money just with a sdcard and not with a MUCH Faster emmc card )
well... it seems the sdcard is the bottleneck i have again - the power of the C2 is awesome ! plays x265 files like a charm and have enough ram and cpu power -
BUT the Menu Navigation is the same Laggy poor slow crap like with the pi2 ! ( well after a speedtest here i get 35mb read and 13mb write ^^ )
and it needs also this 17-20 seconds when i go into a library the first time... ( either its again the slow sdcard or a madnox problem - cause C2 have gigabit lan )
i already post a help request in odroid c2 thread, if there is someone who can test madnox with a emmc card ( read around 124mb and write 80-124mb ) - i hope someone there can help me with this, before i spend more money for a emmc card ( around 50euros again )
i realy hope that a emmc card will speed this things up, because this c2 seems to get a realy great device that will play almost everything !
well, thats it... will report again when i get any news
EDIT:
ok, seems realy like the SD-CARD is the problem - so if you think about to buy a "Raspberry Pi ( 2 or 3 )" or a "Odroid C2" - u realy need a FAST SD Card or when you wanna Buy a Odroid C2 you should buy a eMMC Card ( at least the 16gb version )