Turn Fin?

I have a Sleekcraft 21 Jr Executive (Day Cruiser)with a 5.7ltr and Alpha 1 outdrive. I find that the low speed manueverability is pretty poor. (it pretty much goes where it wants if there is any crosswind) I have thought about installing a turn fin. anybody have any thoughts on this idea.



I am not a rookie boater, had I/Os, outboards, jets, and for the last 28 yrs a Hondo runnerbottom. I can do the work, just wondering if anyone has done this before and how it worked out.



Thanks

Bob

Turn Fin?