Thundercat/Zapcat inflatable catamaran
I bought a thundercat style inflatable catamaran. 4.8m long, open stainless transom, aluminum floor, fiberglass nose, 1.2mm PVC fabric, 30 HP outboard.
It works quite well - it uses extra inflatable hi-jackers to get a V hull shape. These plus the flex of an inflatable and the air underneath make the ride smooth and improve efficiency. Handles surf well - either goes over the wave or through it. Seems best to take the surf straight-on.
I estimate 5 statute miles/US gal with a two stroke engine. Not recommended to store it in the sun. Avoid sharp objects.