But I suspect you will be fine with a 130hp yamaha 4 stroke (or Honda). But if were me I would go a 150hp Etec. They are no different to any EFI engine, ie 4 strokes. You just have to service the petrol filters (should have one in boat as well) and the oil and check a couple of other things and your chances of blowing and injector are no different to any other efi engine, ie 4 strokes, the only difference is cost, they about 3x the cost of a yamaha injector, although you have 4 on a 4stroke. So the real take home is have it (or do yourself) serviced as per the service book. Those items yearly and then every 300hrs of 3 years take it in for its major service, where they will also update any software required etc.

Have you got a permatrim and a stainless prop designed for holeshot? This is the main issue for 4 strokes vs 2. They struggle out of the hole, they get to speed slowly but smoothly. But a permatrim or other foil and a decent hole shot stainless prop can make a HUGE difference getting to speed fast.

Not quite sure I follow that Fizz, you would have 4 injectors on a 4 stroke only if it had four cylinders. A four cylinder E-Tec would also have 4 injectors.  Plus injectors on 2 strokes have to 'fire' on every stroke - so twice as often and they have less time to do so than on a 4 stroke. I should imagine that would require tighter tolerances and possibly lighter components. The E-Tec injector also operates in an oiler environment than on a 4 stroke so that can affect them also.

We have done 2 big trips 10-20 miles off Cuvier from matarangi, and similar off back of Mokes from Leigh since new year.

the newly updated df140 should be available for purchase locally soon i would imagine - might mean the outgoing ones are going cheap - or you have the opportunity to get the 'latest and greatest'