In summary, I ended up returning the phone, but I might recommend the phone to someone who does not have many demands on their phone's performance. I might buy another, but I going to give Nokia / Microsoft a few years to improve the hardware and software.
The first phone simply stopped working. No problem, I thought - there is, hypothetically, a 1 in a 100,000 manufacturing defect in all products and I was just unlucky to have received that phone. Before it stopped working it would not save half my contacts to the phone and deleted a number of contacts. Not a good start (but fortunately I had a back up on my old phone and on my old computer - Windows Phone replicated with People in the cloud and deleted my contacts on my Windows 8 computer). O2 replaced the phone without quibble - customer service was excellent.
The second, replacement phone, all the features did not work. Firstly the phone corrupted the micro sim, which stopped working, live tiles would not update, the bluetooth was erractic, and the colour of the tiles could not be changed. O2 were again great at customer service, replacing the phone without quibble and also enabling my old phone (a Blackberry 9860 over Christmas so my family could contact me.) At this point I had concerns with the quality of the software, and felt I has gone back a few years on functionality (more on that below).
The third phone was up and running - when connected to wifi, people, calendar, and live tiles all worked brillantly. Accessing Skydrive, One Note, and Skype was quick, easy and what attracted me to WP8. On 3G / 4G this was a different phone. Live tiles would not update. After three weeks of use, the phone had a few occasions it would freeze on calls - I could hear the speaker, they (including O2 who called me to find out how I was going) could not hear me. The phone would need to be completely rebooted.
What was more annoying was the fact I could not send text messages or emails if the phone was not connected to wifi or the mobile phone network. I work in London and travel on the Tube, meet people in internal meeting rooms, basement bars, restuarants, and coffee shops. I use the time to respond to emails, text messages. The phone does not allow a message to be sent and held for sending when the phone connects to the network. I felt I had gone back 10 years in technology. O2 were unable to advise, as the Customer Services representatives advised, there are not enough WP8 phones for them to have adequate knowledge of the phone (Android, Blackberry, Apple - yes). Compared with my old blackberry, there were other features which were not as flexible, or could not be customised, but hey - it is a new operating system, and these quirks I thought I had to live with.
The final straw was twofold: the phone would not connect automatically nor stay connected to the Microsoft designed Blue&Me bluetooth connection in my car. My Blackberry connected when I bought the car, and would automatically connect and stay connected (without intervention for over two years (even when in the boot)). Lumia 925 failed miserably. Then the LiveTiles stopped updating and downloading - Bing News, Bing Weather, and Twitter(!). I would get on the Tube to catch up with the News and twitter posting (in a 4G location), to find the phone had not updated since I was connected to Wifi.
I did a lot of research on this phone before upgrading. It is too glitchy with faults arising too easily, not customisable enough, and not enough training at O2 to be able to advise on the phone. Bluetooth connection (including with a home music system) is not good enough.
On the good side this was a beautiful phone to hold. Light weight, great responsive screen and benefiting from Bing, a Microsoft Windows Apps like skype, Skydrive, Kindle, One Note which worked very well on 4G. The camera was brillant and photos fantastic. Calls were very clear and people commented I came through loud and clear.
I want Microsoft / Nokia to succeed. Competition and innovation for Android and Apple is good. If you want an easy to use, great in hand phone, and your not bothered by customisation features it will be a great phone to use (your elderly technophobic Mum or Dad might get along with this phone). For serious prefessionals, or those who are demanding of their hardware and its features, it is not quite there yet. I will come back to look at buying a Windows Phone in a few years. I suspect it is on a journey, but the quality is not yet there.
Track usage, upgrade and get support with the My O2 appDownload My O2