I have owned these in the past, while it is good for the price overall I would say they sound mediocre.
Mids were meh, I don't know what your definition of amazing mids are. Highs were grainy, and lacked a lot of definition. Bass is ok, nothing too bad about it except it doesn't extend too well which is to be expected of a single armature iem. Soundstage was pretty big but nothing too special.
Overall sound signature is leaning towards dark. In my opinion, the RE0 demolishes this in terms of clarity in the lows, mids and highs. The RE0 is just such a better and more cleaner sounding iem.
Also I didn't like the cable for the SuperFi 5, the cable feels tacky and is microphonic as hell worn down. The 3.5mm plug doesn't have a proper strain relief either and is a straight plug.
Would you believe that the RRP for the SuperFi 5 in Australia is $349.00? What a pathetic joke, we Australians are the butt of all retailers.