Well, I'm not a UK guy, so I'm not sure why I was reading here... But my two biggest contracts were Visteon and Ford back when the 'Baby Jag' was released, so I remember quite a bit about it.
From Ford's point of view, this was the Jag that nearly killed Jaguar, and probably was one of the final nails in Jaques Nasser's coffin. Not only could he not run a major market automaker, he couldn't even run his pet project PAG right! The X-Type was supposed to be an entry-level Jag, but it was widely panned everywhere, and really hurt the status symbol standing of Jaguar Cars. It had the rare trifecta of losing money, prestige, and angering more senior customers.
That's not to say it's a bad car, though. The Contour/Mystique/Mondeo were good cars, but had some unusual quality issues. You'd either have no problems, whatsoever, or you'd get a lemon that never would be right. There was no middle ground. It was either a great car, or the reason that person swore to never buy another Ford product. The Jag based on it had better looks, better handling, all wheel drive, and nicer interior. I'm not sure it was spared the quality issues, though.
Personally, I'd have a hard time recommending a late model X-Type. From a performance point of view, I think there are a LOT better choices in that age/price range. From a status symbol point of view, I think there are better choices, as well.
But, if you really like the looks of it, and have always wanted a Jag, it's a relatively low-cost way to get in one. That is something you can't cross-shop.