dinghy cover

What covers are the best for protecting the dinghy, keeping water out, and staying on while under way? MM

For those of you who cruise with a dinghy on a submersible swim platform, do you cruise with your dinghy cover on or off? We've been cruising with ours on but often will have water pooling into the dinghy cover when in rough water which worries me because of the extra weight that it's adding to...