It doesn't imply lack of quality either. That's what testing is for. All else remaining equal a higher pixel count can be beneficial - if done right (see Nokia). So it's quite impossible to pass judgment at this point in time.
Umm, your camera specs for the One M8 are incorrect. The two rear cameras are the 4 MP Ultrapixel, and a 2.1 MP camera ("for depth"). The front facing "selfie" camera is a 5 MP (not 2.1 as you stated - that's one of the two rear-facing cameras).
The rear-facing camera setup is okay. I wish it had been an 8MP Ultrapixel camera with OIS, rather than the two camera setup. 20MP isn't needed, but if it does come, and is a quality camera choice (Sony?), I'd gladly take it over the duo cam.
The 4MP Ultra Pixel sized pixels was awesome. If they could of just enlarged the sensor large enough to keep the ultra pixels the same size (2.0um i believe) but up the resolution to 8MP as well as upgraded mechanical OIS It would probably be the best camera.
Low light performance should be the number 1 consideration. Since more often then not when you want to take a random spur of the moment picture lighting isn't usually the best set up.
I thought I posted this....wonder if it was removed.
I'd like to see the ''engineering process'' improve to where they're able to remove the black HTC bar at the bottom. Grow the display or shrink the device but M8 is such a large device for the screen size.
Looks like the same old crap. HTC build quality is nowhere near the level of hype, especially when some people tout it as the android answer to apple. I have a few friends with m8, the vast majority want to go back to iPhone, and the only one sticking with it is a Taiwanese guy insistent on everything Taiwanese lol.