Ooh sauce!

We've had Marmite XXX, HP with Guinness and now ... Heinz Tomato Ketchup with balsamic vinegar. Given that the regular version already has vinegar in it, would there be an amazing taste difference?

No.

As with the Marmite, the difference is negligible, except in price (I've not tried the HP due to my Native American/Japanese-style alcohol intolerance).

But the black and silver bottle is terrific!