Flavour of Kumquats?

I have a question for folks who regularly make Kumquat marmalade... how does the flavour compare to Orange Marmalades?

If you could place a finger on the scale of Seville - Blood Orange - Navel, where would you put it? Is it a bright flavour like simple Orange or is it more perfumed as a Tangerine or Mandarin can be?

I have already made my supply of marmalade for the year but there are still some spaces left on the shelf...