What do you mean by "good for your boat"? If you mean what is the best prop for your engine, then the answer is whichever prop lets your engine turn at 5500 RPMs with the throttle wide open is the best for your boat.
It's hard to guess accurately what prop that would be since there are so many things that can effect your final speed. Amount of fuel, number of persons on the boat, food, bait, tackle, anything that adds weight will effect your top end speed. Additionally, if your hull is smooth or rough will effect it also, plus how you have your engine trimmed... All these things can and will have an effect.
As both Spareparts and Tsubaki have already said, try the 19 Pitch prop first. If your engine RPM is right around 5500 rpm then it probably is the best one for your boat. Only you can make that determination after trying it though.
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1987 V20 w/1987 150HP Yamaha on a Shoreland'r Trailer
1978 16.5 Airslot w/1996 120HP Force on a Four Winns trailer
1996 V21 w/1993 200HP Mercury on a Shoreline Trailer
All towed by a 5.7L Hemi Durango.
If God didn't have a purpose for us we wouldn't be here, so
Live simply, Love generously, Care deeply, Speak kindly.
(Leave the rest to God) 
Silence, in the face of evil, is itself evil. Not to speak is to speak, not to act is to act. God will not hold us guiltless.
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