5 million is a lot of miles. I can see that you would have a loyalty to Jags. Note that my comments and comparisons are directed at the worship of rice. I know that some European brands are superior to Asian brands. That said, I would still buy American. I would buy a Ford/Jag long before I would purchase rice, however.
Personally, I buy whatever I want to drive that fits my needs and my wants the best. For me, it's usually a Jag of some kind, but I have had other cars - everything from a BMW 750iL to a beat-to-hell Toyota pickup truck. My last daily driver (when gas prices spiked) was a Nissan 300ZX Turbo. I've bought American, Japanese and European.
I have no illusions about Jaguars, I've had too many of them, and no, they aren't total paragons of reliability. But they are better than the domestic product overall, sad to say.
From my experience: The Japanese do build good to excellent cars and there are some that I'd like to have, but most of them lack character and "soul". The American products just seem bland and uninspired at best, and gross money pits at worst. My Jeep has been exhibiting the latter behavior lately, as did the F-150 before it, and it's going away. Ironically, I'm going to buy a Land Rover Discovery instead, because it will probably be more reliable.