Finally got a set of Mitcho's Sup fins after trying a demo set a few months ago.
These fins are amazing. I have run them as a thruster set as well as in a quad set up.
The side fins measure up at 4 7/8" high with a base of 4 5/8", the rear is 5 3/4" high and a base of 5 3/8".
Every other fin set ups for me have felt like a compromise, but these puppies feel spot on. I have surfed them in a variety of conditions including small beachies, point breaks, double overhead river mouth and an offshore reefbreak... heaps of drive and reliable turning.
If you're not happy with your current set up or looking for that little extra performance then invest in a set of these, as it may be what you've been looking for.