I have had good luck with Doelfins but you should consider it a last resort.First you should fine tune the setup of your motor.Verticle height and trim are important.You should begin with the antivent plate even with the bottom of the boat.Then raise it 1/4 inch at a time till juty before ventilation becomes a problem.
If you can gain 1 inch it could give you 2 to 3 mph.It may halp hole shot a little as well.
When trimming if one notch seems not enough and 2 seems too much you can make or buy wedges to give a 1/2 notch.
Fins can work wonder fully you need to be careful to size it right and install it correctly.A properly installed fin will vastly improve hole shot,and level the bow and may
lessen bounding in the waves.It also will assist to stay on plane at lower power.It will generally lower top speed.
It can cause weird handling problems.And you may use more fuel at wot but you may save fuel at lower speeds.You should check to see if they have smart tabs for small boats from what I've read they are close to amazing.Again fine tune your setup before doing either one.
If you can get the tail out of the water once on plane, you'll get the advantages without suffering the lower speed you'd get from dragging it through the water.
thanks for the info fellas, I hava a 14ft boat with a 15 hp 4 stroke was thinking of trying one to get a litlle bit better hole shot when i have anougher person on board. boat works great when I am by myself,