There are a couple of things to consider - he mentions wanting to sail in a popular class. Broadening on Rich and Chris' suggestion of the Tiger, I think he would find newer F18 designs more weight-tolerant, both in buoyancy and power. Some platforms carry weight better than others and the racing is equal; 400 is a little much for any F18, though. The problem is that there aren't other options for a popular double-handed multihull with a competitive fleet that will carry 400-pounds in his area. There are some Nacra 20s in the San Diego area, but they don't travel.

I'd recommend F18 (not just the Tiger) to meet his stated needs.