Hi kjbacon:
We got to do both many times from the Quest (2019). In Antarctica, the zodiaks were included so we got to do 6 of those trips, but we had to pay for the Kayaks. Best money we ever spent! If the water is calm, they are so peaceful. And you really did not need any previous experience.
We initially signed up for 3 kayak trips just to make sure that we would get the opportunity to do at least one, as the weather in Antartica is unpredicable (days 1, 3, and 5 all worked out, but days 2 and 4 had to be cancelled). But after clear blue sky, no wind, glassy water, outstanding support crew and top notch equipment, we kept the other two trips and were lucky to get to do them all. One difference was that in Antarctica, we got to do both the Kayak and Zodiak trips every day, so we did not have to choose.
Each trip was different, but we would not have given up any of them. And since we were taken to the Kayaks using the Zodiaks, we actually got to do 3 additional zodiaks trips. They took us to spectcular locations separate from the Zodiak locations.
We are doing Alaska in a few weeks on the Odyessy and will opt for the Kayaks. If the weather is not ammenable to kayaking, you might still get to do a zodiak trip.
Hope this is useful!