I bought a PS Vita at launch and used it for almost 2 years, before idiotically leaving it on the floor and standing on it, cracking the screen (oops). I contacted Sony, who wanted £123 for a swap service, and couldn't guarantee I'd get a new console, and would possibly receive a "remanufactured" (aka refurbished) unit.
So I looked on Amazon and found the Vita 3G Disney pack for just under £160. I didn't need the memory card and wasn't interested in the included games, so these can be sold on again for around £40 - £45 in total, plus the broken console can be sold for around £30. So all in, a much better deal than Sony were offering. As the new model has just been released, it might be worth waiting a while to see what deals become available for the old model.
The Vita itself is fantastic. Several firmware updates have added improvements since it was launched, including a much improved web browser to rival a touch screen phone. There's also an email client and some apps, such as a Facebook app. There's a great selection of games from all genres. My favourite genre is racing, and there are plenty about, including Wipeout. There are also some good adventure/ puzzle games (Uncharted) and platformers (Rayman).
The graphics are stunning, much better than anything produced by Nintendo, and better than any mobile game you can get. The front and rear touchpad, as well as the camera add extra gameplay dimensions to various games.
Another positive with the Vita is PSN integration. For £40 a year, you can sign up to PSN and download new games every month. As well as big titles, there are also some great indie games on offer for free or discounted prices.
The battery life is the only let down with it, but there are things you can do to minimize it, such as turning down the brightness.
This on its own is not enough to knock off the fifth star. Highly recommended product.