Coming from the M7 (and having owned the DNA, Rezound, and Droid Incredible), I honestly believe this is the best phone I've had so far.
Pros:
- Battery life has been quite good for me so far, even with heavier-than-normal usage and without having been through a full cycle yet.
- Reception and data speeds have both been better, presumably due to the M8's built-in support for the AWS band on Verizon's LTE-A.
- The device runs cooler, and has not heated up yet through usage.
- The Gesture Controls are fun and make it more convenient for me to use my phone.
- The build quality is, as expected, superb and the phone feels great to hold and use.
- The vibration is very quiet (when your phone's on a flat surface, i.e. a table) - when it vibrates, it's not loud or obnoxious. This is a massive improvement over my M7, where the vibration was so loud i would have to set my phone on silent to avoid bothering others at work.
- There is a wide range of volumes that the phone can output - the speakers can be anywhere from really quiet where you can barely hear anything, all the way to being louder than laptop speakers.
- The power and volume buttons seem to be better-constructed than they were on the M7 - they are actually sticking out as opposed to being completely flush, and have more tactile feedback.
- Everything is extremely fast and smooth, and as a whole, I love the new Sense.
Neutral:
- The on-screen buttons do take some getting used to. On the bright side, because they are on the screen, it means I don't have to stretch my fingers as far down as I would if they were capacitive buttons, thus making the phone slightly easier to use.
- Because the finish is so smooth and shiny, I constantly feel like I might drop the phone if I'm not holding it carefully.
- Not sure how I feel about the power button being on the top right now instead of top left, but with the gesture controls, I'm hardly ever touching the power button anyway.
- I'm not a huge photography person, so perhaps my opinion isn't accurate; however, I feel like the camera's more than good enough for my needs. It doesn't necessarily wow me, but I'm not disappointed by it either.
Cons:
- The gesture controls are designed to work when you pick up the phone; this means they don't work when you have the phone laying flat. If nothing else, I'd like to be able to double-tap when my phone's on my desk so I can see notifications.
- The phone is slightly larger than the M7 was; for people with small hands, it could be difficult to operate the phone with one hand.
- I somewhat prefer the less-rounded corners on the M7, but I can see how that would make the M8 seem even larger, so I'm getting used to it.
- All of the icons in the Settings menu are now grey, as opposed to the color icons that older iterations of Sense had - makes it slightly harder to find things.