center fin is typically 6-7", depending on the size of the rider, the wave, & preferences. at around 200lbs, i prefer a 6.5".
the extreme (15-20°) cant of the 4 side fins allows the board to hold really, really well in steep faced waves, which is why a lot of people seem to like them for barrel riding boards (not to mention that they're super fast, so getting swallowed up isn't as likely), & they go rail to rail quite easily...provided you know how to use your rail, & don't just try to pivot on the fin cluster.
Nj...I loved that Wynn bonzer at the top---great tint and a bit better looking than a bumblbee imho. Such a beauty...even floated u a trade on the one below it. Wish your current one was a few inches shorter...
live4truth, that top 5'10" is one of those boards that i wish i'd never gotten rid of! haunts me frequently...such a fun board! i used a 6" fin in it...one of the only bonzers i've had that worked well w/ that small a center fin.
please take my current one off my hands...it needs a good home & is just taking up space in my garage!