Actually a good deal more spit than we expected.. We never anticipated how much was actually required till we saw the tubes and the marking. The bottom is funnel-shaped, so that's not too bad, but then it takes a good bit more yet to reach the required amount. Not sure what would happen if a sample is submitted only half-full or at least below the mark. Throw in a bit of dry mouth upon waking and we found ourselves spending up to 20 minutes with it. Probably the nervousness of knowing that we HAD to do it didn't help. It delayed our medication schedule. Given the choice, at this point, between going with Viking and having to do this, and going with a different line that doesn't require it - we'll probably opt for the one that doesn't require any testing except for the pre-cruise. I'm saddened by this however, given that I am (or at least was) hoping to do more cruises with Viking - and have two booked for '23.