I'm still trying to pinpoint the moment at which I completely lost interest in Jaguar's products. I remember going to a manufacturer driving day several years ago and trying out the previous XF in both its diesel forms and the XF R, and driving the XJ Supersport. Loved all four.
But I remember being disappointed by the F-type the first time I drove it, not particularly liking the XF RS when we did a super saloon group test (once again, mainly let down, again in damp conditions, by weirdly springy and feel-free steering), and being outright intimidated by the R AWD on wet Welsh roads.
I'd like to have a go in an old X300/X308-generation XJ at some point to see what it was like when Jag was way behind on things like tech and quality but far better than its competitors for things like steering feel, ride, and dynamics.
Though honestly, my favourite Jag at the moment is still probably the current XJ. The interior is still wonderful and I suspect in 3-litre diesel form it'd be a lovely thing to knock around in day-to-day.