This Christmas my wife bought me a Kindle Fire. Originally I wanted a Nexus 7, but was tempted by a Black Monday offer of £99 for the basic Fire (normally £129). There is also a more expensive HD version, which also has Dolby sound, for £159; but in my opinion you are getting dangerously close to Nexus 7 pricing at that point.
I am a great fan of the 7 inch form factor. Personally I would be embarrassed to carry around with me a 10″ tablet, but the smaller book-sized 7″ tablet is fine. Without a case, it will even fit into a suit jacket pocket.
My hope for the Fire was that it would be a quality device, being sold cheap as a loss leader for Amazon, but more to the point I hoped that it would still be usable for email and web browsing and that I would be able to find at least some of my favourite Android apps in the Amazon app store.