After upgrading to the M a few days ago, I think I've come to a few conclusions about the device. Keep in mind I upgraded from the OG Incredible, so I may be easily impressed by some things that people coming from newer phones now consider standard, but in that time, my wife has owned a G-Nexus and a Razr (her current phone), so I'm not completely lost when it comes to newer devices.
PROS
Build quality/form factor: The first thing I thought when I picked up the phone was how thin and light it felt in my hand! It made my DInc feel like a brick, yet it has a bigger screen in just about the same size phone. It makes my wife's Razr feel absolutely huge. I love the screen size and the bezel-less (or at least bezel-reduced) edges; I can reach pretty much the whole screen with one hand, yet still have the benefits of a relatively large screen (I can't imagine using something as big as the Note or GSIII). The build quality is also great - it is Motorola after all. With one caveat (more on that soon), the phone feels absolutely solid, and is great ergonomically.
Processing power: If specs like this are considered mid-range now, consider my mind blown! The S4 is an absolutely fantastic processor, and makes my DInc feel like Windows 95. I've had almost zero lag while doing much of anything on the device; it keeps up with every thing I can throw at it - music, video, gaming (no lag at all when playing Granny Smith or Ski Safari). It runs silky smooth, and with Jelly Bean coming soon, I'm hoping it'll only get better. The phone is so smooth, it runs almost like - dare I say it - an iPhone!?
Cell radio: I know some people have said they've had some connection issues, but with 4G/3G, I've had no issues at all. 4G is lightning fast, and I usually get 3-4 bars easily here (I live in a relatively major city also, so keep that in mind). No signal drops, no connection issues here. Appearantly your mileage may vary.
Battery life: First day I had it, I take it off the charger at 6:45 am, and when I get home at 4:00 pm, my battery is still at 80%. Granted, I was on Wifi most of that time, and didn't use it a whole lot, but it still blows away anything I could get from my DInc, or what my wife gets with her Razr. Battery life since has been great still; I never have to worry about running out of juice or looking for a charger. Now when I switch to 4G, it drops a good deal quicker, but I think that's to be expected. Overall, the battery has been great, unlike almost any smartphone not named the Razr MAXX (and don't even get me started on the G-Nexus!)
CONS
Wifi radio: The connection picture hasn't been all rosy for me. Rarely (maybe once a day), when I'm on Wifi, the phone will kick me off for about 10 seconds and back onto 4G. It's certainly not a big deal, and the phone seems to recover very quickly and reconnect, but it can be annoying from time to time.
Power button: This is the only bad part of the build quality of the phone. It may be just my imagination, but the power button on mine feels just the slightest bit loose. It functions just fine, and it doesn't feel like it's going to come out or anything, but if you're anal about things like this (like I am), it may bother you. I have an Otterbox Commuter on the way from Amazon, so I don't think it'll be an issue at all after I get that on, but if you like to have your phone naked, this may or may not be an issue for you. I just get a little antsy whenever I push the thing.
Overall, the phone has exceeded all my expectations. It has all of the specs and bells and whistles of your higher end GSIII and Razr HD, but without the higher price tag and absolutely huge feel in your hand. Some people like enormous phones; I can't say I'm one of them. I haven't had much of a chance to try the camera, but I use the Camera Zoom FX app to take pictures, and the few I've taken seem to be fine. If you're looking for a phone with a smaller form factor (and when did 4.3" become small!?) with amazing processing power and great battery life, try this one out!
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