Hi Peter,
You have my respect as a calming influence on all of the "OMG it's a risky buy" when considering a secondhand Jaguar
Little bit of history...
Back in 1983, I made the biggest mistake ever and bought an 4.2l XJ6, which did 6mpg and only one fuel tank that worked). WTB said "That has to go!", so bought a Ford Capri JPS. (Black, Gold stripes, gold seats; you get the picture!)
History has furnished me with some lovely and some not so lovely cars, but I've never lost my joy of driving.
However, while I always listen to your sage-like advice, I've recently swapped from Millers to Wynns. It seems to make the running smoother, and certainly more responsive.
Happy bank holidays! And thank you so much for your insight (also applies to others, too numerous to mention)