Hey Nathan,
Been using a compass ever since I've been sailing.

It's a large kayak compass large enough to be seen from every point on the boat, even trapped out on the stern. Many of the H16 sailors use to laugh at me for having one but they obviously didn't understand it's principles. Always sailing in the ocean (with few land references), I found it to be very useful.
I used a plastic base permanently attached to the (right) front cross bar but moved it to the left side after installing the spinnaker as some of the spi hardware needed to be located on the right. The compass attaches to the permanent base only requiring a twist for a quick mount. Ocean or lake, properly used, will be a plus !!!