I am from the UK (well, Scotland), but I can say that the Jag X-Type, although being effectively a Mondeo Chassis, it's nothing like the Mondeo for what it's worth. Rule of thumb is, for me at least, if it's got decent mileage for it's age, is in good condition, and is reasonably priced then go for it if it's within your budget and you like it. I own a Saab 9-3 Hirsch and it's constantly getting compared to the Vauxhall Vectra, and although it shares the same Wheelbase etc, it's nothing like a Vectra and similarly the Jag is nothing like the Mondeo. The refinement and the drive in the Jag is very special in comparison but conversely it's not a fully fledged Jag as you would expect but then again, that's reflected in the price. If you go for it, I wish you good fortune with it.
John