Honor Holly 3 has below disadvantages.
a) NO OTG support available
b) company should provide headphones in the box.
I have used this phone for almost about 3 months and i did not find any major drawback. The only suggetion to the company is to provide at least pair of headphones in the box.
Honor Holly 3 comes with 16GB Internal Memory (ROM) which can be expanded up to 128GB via MicroSD card.