I was interested to see how similar the B-25 and Marting 242 are. The B-25 is usually rated at 138 in stock configuration, (although most owners have converted them to masthead spinnakers and taken the rate hit)
The Martin 242 is rated around 150 if I got the correct data.
If the B-25 has less sail area and weighs more, I wonder why it has a faster rating?
I think the hull design works very well. It looks very similar to many newer designs. It is the appendages that are out of date, not the hull. So I update the keel and rudder, along with extra roach in a new main. The shrouds are inboard, so you can use a 155% genoa on the boat or reduce to a jib in higher winds. I am very happy with my setup. It would cost upwards of $50,000 to equal its performance with a new boat. I like the symmetrical spinnaker for our lake sailing.