C/B the depth gauge for dorks
It would be difficult to compare all C/B boats in one fell swoop, that said the Helms 25 is the only Helms w/Centerboard (24, 25, 27, 30, 32) and it has a well pronounced keel that allows it to sail with the board up quite effectively. The board is most noticable when beating into the wind the centerboard down helps the pointing.
As an amature sailor I have welcomed the pennance and privacy of going below to crank on the C/B winch, 16 full rev's on mine will release me from the shallow water that has trapped me yet again. It may be good to point out that the rudder is two part and also kicks up from the force of earth impact. The force on the rudder is then magnified, it's like losing the power steering on a truck.
The Helms Centerboard is 1" thick steel weighing in at 300# and lowers the center of gravity as well as drawing neat lines in the mud prior to earth impact, see above.