I'm not sure what to do here.
My existing 6hp engine performs pretty well on the boat, and it will do about 15mph with two adults on board.
It is a bit noisy when planing, but I guess any outboard motor will be noisy when you are sat about 20 inches away from it....
I guess I have to decide if the extra few MPH will be worth the £1,000 or so it will cost me plus my existing engine.
Probably not is my thinking at the moment. Better to wait a bit and then buy a bigger boat for open water use, keeping the SIB for the canal and Norfolk Broads.