Charlie,
A medium sized Fortress or Guardian makes for an easily deployable stern anchor and as a kedge deployed from a dinghy. Hopefully you won't be using the kedge anytime soon. If you head south of Mex then you will end up a in number of open bays that are susceptible to the ground swells. We rarely used a stern anchor in Mex, although we shared anchorages where half the boats were on stern and bow. Using a harness on the bow anchor doesn't really work because the wind and the currents are not consistent enough. So a stern anchor to keep you into the seas is needed on a few occasions. We've deployed a stern anchor 2 or 3 times in the last year. It s way down the list of choices for me, but some places you just gotta do it.

Paul L