There is quite a bit of internet chatter about softness at any aperture at the extreme ends of the lens (16-80) - I suspect that some comes from sample variation and others might come from the fact that on the whole any zoom lens where the longer focal length is more than 3 times the shorter focal length is potentially compromised in design. Most 'great' zoom lenses are a multiplier between about 2.5 and 3.5, Fujifilm's less successful ones (in terms of IQ) are 5x (16-80) and 7.5x (18-135) - this though isn't unique to Fujifilm, but fairly true across most lens manufacturers.