I dont have practical experience on MiniION Oxford Nanopore,

But am works in Ion Torrent, Illumina, Agilent methods.

As per my understanding, MiniION can give us a rough idea about the microorganisms 16s Ribosomal RNA data, with 96% accuracy.

Which can be useful to detect at Genus level, but not at the Species level accurately.

Further details I can share, if you ask specifically.

Surely, 

http://www.science-practice.com/blog/2016/05/18/york-minion/

read here.