Go for the fin, unless you really need the shoal. The difference in performance is substantial.
Well we certainly have different definitions of substantial
This topic comes up a LOT
on Sailnet, and I'm always amazed at the bad information and how many folks get their panties in a bunch over this.
Wing keels are a bit heavier to compensate for the reduced lever arm of the shorter keel. The idea is you apply a bit more force to the lever arm (keel) via additional weight to get the same effect attained through leverage with a longer lever (deeper keel).
How much weight? In the case of my Catalina 30 MKIII the difference is only 100lbs in a boat weighing 10,300 lbs. In other words the weight difference is not substantial. In fact I know
I have over a hundred pounds of tools, spare parts, clothes and food on board. Most boats do and we don't give it a second thought.
What about performance?
The PHRF rating difference between a Catalina 30 fin and a Catalina 30 wing is 9 seconds per mile because there is a slight
difference in pointing ability.
Let's quantify that slight difference. 1 MPH is 3600 seconds per hour. 9 seconds is 0.0025 MPH. Would you call that substantial?
The condition of your sails make more of a difference. More importantly the skill of the skipper will have a much greater impact than the type of keel
If you're racing seriously you want every advantage so getting a fin is a no brainer. But if you're cruising in thin waters I doubt anyone here could sail two otherwise identical C30's and be able to tell you what kind of keel they had based on how they sailed.
As for hard groundings I'm on my second wing keeled boat and have gone hard around once with each. The first was a C22 that went aground on the Delaware River on what I would describe as a mix of mud, sand and industrial waste. We broke out hoagies and cokes and waited about an hour for the tide to lift us off. The second was on a sandbar in the Barnegat with our C30. It took a few minutes to work her off, but it wasn't a huge amount of drama. I can't comment on the stickiness of Chesapeake mud as I have no experience with it.
Bottom line - pick the keel that makes sense for the water depth in your area and go sailing. It's just not a big deal.