Remember that a vintage Jag isn't a new Lexus, the paint is supposed to look a certain way.
I kinda like how the Collinite 476S looks on older Jags, gives what's *IMO* the correct "period look", especially if they've been reshot with b/c paint. Similarly, I don't go for the "ultimate level of gloss" with those as it's simply not period-correct for concours purposes (and I've been over this in depth with the JCO's chief concours judge).
Watch that KAIO doesn't give a funny, "sealant" look. I use Autoglym SRP instead on older Jags (both ss and b/c).
I did my pal's '60 MKII with M105/M205/SRP/Collinite 476S and it took first in class at last year's Stan Hywett show and subsequently did well in the season's JCNA concourses. I was worried that the M205 might've left things just a *bit* too glossy, but nobody else saw it that way. The aforementioned judge (decades of experience) thought it looked just right and quizzed me extensively about what I'd done.