I had the BB z10 for 48 hours testing it, and I liked the hardware and the OS for the most part, but the lack of app's I need in a handset and concerns over future apps arriving on the platform put me off taking the final plunge.
The screen was very sharp I thought, although brightness wasn't staggering in the handset I had.
I loved the little animations and at times there was a really great deal of attention to detail. The swipe to awake the phone was very handy. I also didn't find the phone slow or unresponsive except when it was trying to run an android app, which reduced performance for all open apps - as well as being very sluggish in the android application.
I liked blackberry HUB - but could see how it might not appeal to some. But I like unified in-boxes for all my data email accounts / networks feeds.
Bluetooth I had issues with pairing my car stereo. It would connect when fresh, but should I get a phone call via bluetooth, when the call ended - i had to restart the device or mess about enabling and disabling and re-connecting bluetooth to my car stereo once more, and that was annoying.
To me the BB Z10 is probably the best 'first iteration' of a mobile OS i've seen and certainly an improvement over both playbook OS 2.0 and Blackberry 7.
But yes there are some rough edges.
I hated how BB App World doesn't differentiate between what is an android port and what is a native application. It's annoying, and feels disingenuous. Also the quality of some of the apps is shockingly bad. I downloaded a number of them and deleted them almost straight away. One even forced me to restart my phone to stop it. It's like BB had just approved any old trash to increase the number of apps on the store - without any quality control.
I suffered through that with Google Marketplace (before it was Play store) and when there was an over abundance of copycat junk apps that simply didn't work or were bug ridden on your device. It was inexcusable in android world, and in BB App World even more so given the competition it has to face.
I thought call quality was very good on the device though, and the keyboard was good too. Really liked the auto suggestions. Messaging on it was very good.
It has a lot of promise, but a lot of rough edges too. Had it had the app's I use daily - I would have stuck with it. But it didn't and I don't trust it would get them after the rather barren App World on playbook and my experiences of my Bold 9900.