Given that you want to edit word docs etc (and this is the Windows Phone section of the forum ) Windows Phone 8 should be at least an option as mobile office comes preloaded on all WP8 handsets. I couldnt find the Lumia 925 on the vodafone website but unless I am mistaken it is still available in stores which would be a good option.
The 925 also features a great camera & software, excellent screen especially in sunlight & Here Drive GPS software with offline maps to name a few.
If you have a Windows 8 PC there is good synergy between the 2 devices. Something as simple as having your contacts syncronised across your laptop & phone without having to do anything is useful esecially if you are using both for email. I am sure you would be able to do this with googles services but I really like how easy the 2 work together.
If you want something cheap the Lumia 520 is a great option for the price & performance wise stacks up well against any Android handset on or around that price point.
At the end of the day it comes down to what is important to you. Android has more apps but there are still plenty available for Windows Phone plus depending on what your needs are this may or may not even be a factor.
Thank you to all of you for your replies. I settled for a Nokia 925 as I am not that fussed about all the Aps, but did want Windows, and having office available as is was a key consideration. Combined with a great camera and all the maps, it was stacking up very highly. The deal clincher though was taking a testdrive in bright sunlight and comparing it to a ?Sony. The readability between the screens was so different and the Nokia really stood head an shoulders above the others at that point.
Thank you to everyone who helped me make this decision.