I'd be really interested to know how say an 11-12m RIB like a Stormforce performs in the same conditions as a similar sized Halmatic/Interceptor etc. There's a commercial Halmatic Nelson 40 and an Interceptor 42 here and the Halmatic I think is generally reckoned to be the better rough sea boat, where the Interceptors slam and jump over a wave, the Halmatics go through it.
I would be really interested to see how any 11-12m RIB would compare. I also suspect the lack of weight might make it behave quite differently, the Halmatic in that size weighs about 16 tons IIRC, though that can also make it a bit of a submarine. The drive is also a factor, shaft drive is the strong preference here, jets are a waste of time because they fill up with kelp, and sterndrives only work when the props are in the water.
An opportunity for a good Powerboat & RIB magazine article there, compare and contrast a 12m Interceptor, Nelson, catamaran, RIB and gin palace in the roughest water you can find around the UK