Doel fins get my vote ...
Another vote for them - on my Futura 4.2m with a 50hp Yamaha :-
- Less bow rise getting onto the plane
- Much smoother ride (definately smoothed out up & down motion)
- Lower speed planing (on average 11 knots compared to 15 without) - in a speed limited harbour I could just about stay on the plane at 8.7 knots on the GPS which helped fuel economy drastically
- Less bow rise pulling ringo or waterskiers
On the other hand :-
- Reduced top speed (couldn't get above 27 knots - but to be fair this is a combination of a cupped stainless prop limiting WOT to 4700rpm and the doel fins)