Cam compares the specs and performance of the two new HTC One-series phones. Although it's noticeably lower specced, the One mini 2 doesn't give the impression that it's a low end device. It looks and feels great and performs well on a number of fronts.
If you want an HTC One but are put off by the size, it's difficult not to recommend the HTC One mini 2. It's a fantastic small phone.