Have had the phone for a few days, posting some observations. Please keep in mind I don't believe in buying phones with a carrier contract or paying 400+ for a smartphone, so my observations will likely not apply to people used to carrying high-end phones.

Pros:

• The phone has good connection on both ATT and T-Mobile, and is pretty fast (compared to my Nexus 4 and Nexus 7 LTE).
• Tethering works on $25/3mo/1GB ATT DataConnect plan - so no AT&T making sure I have the 'right' plan (iPad Mini and Nexus 7 looking at you here).
• The camera works well, and the Best Shot feature is quite useful.
• The gestures are helpful, perspective control is kind of neat, but only mildly useful (there are some included games that use it but I didn't really play them).
• Prime is GREAT (but I still might be too cheap to pay for it on my own )
• I am a sucker for phones with Gorilla Glass on both front and back; it's beautiful.

Carousel is useful and annoying at the same time. I like the additional information shown on the lower half of the screen, but I wish I could control what shows up on the carousel.

Cons:

• Exchange email can't use security certs provisioned from Mobile Iron - so no work email.
• No Google Play Services - so side-loading is only partially successful. Hangouts doesn't work at all.
• No offline maps - native app doesn't seem to support it, and Google Maps doesn't completely work

I think it will work well as a travel phone/hotspot, but doesn't quite have everything I need, so I will keep carrying my Nexus 7 LTE too (with a side benefit of having simultaneous access to Verizon+AT&T networks).

The Amazon App Store is definitely more limited, but aside from what's listed in the Cons, I can live with the delta. I was able to sideload Google Voice, and Groove IP is available in the app store, so my VoIP calling needs are addressed. Call quality is quite good, in case that matters to anyone