As we all know, human hearing is completely subjective and people have different preferences. When I received the UA5 and first tried it with my iPhone, my first impression was that it is very UNDER powered. After learning the settings, I run it in HIGH POWER mode at about 70%. I also realized (but should have known) that the UA5 does NOT do MQA. But MQA makes up less than 5% of what I listen to, and the truth is, in a “blind taste test” I can’t tell the difference anyway. As to power, it needs to be set at the higher end of the scale, but it is able to drive my HIFIMAN Sundara so I can’t complain. It drives my DUNU SA6 just fine. As for sound, I am comparing it to my iFI HIP DAC V2 (my “go to” DAC/AMP, but not as portable), THX Onyx and PAW S2. Here is where subjectivity comes into play. To me, the UA5 sounds “better” than the Onyx and definitely better than the S2. The HIP DAC V2 has more “punch” but not significantly more than the UA5. For me, punch is about dynamic range, not loudness - instantaneously going from a quiet passage to a demanding drum beat or bass note for example. It may be more accurate to say that the UA5 sounds “different” rather than “better.” Only you will know what “better” or “best” sounds like to your ears/brain. Most, if not all, of the new DAC/AMPs sound amazing and in a blind “taste test” almost impossible to tell the difference. As for build quality, the UA5 is small, well made and the built in battery is a unique feature that prevents my iPhone from telling me “The Attached Accessory is not compatible with iPhone,” because of too much power consumption. In conclusion, I now find myself using the UA5 more often, which is the real test - what device one actually uses.