I had the same dilemma. I originally ordered Turbo Blue, as I think that the S-Line looks really good in that colour. After much thought and discussion - and a brief flirtation with the dark blue - I switched to Daytona Grey on the grounds that I have specced the S-Line with standard suspension and was concerned that the Turbo Blue (which is a more attention grabbing colour) didn’t suit the higher ride height. My personal decision aside, I’d say that the Turbo Blue gives the car a sportier look and the Daytona Grey a more refined one.
The thing that mystifies me is that, free colours aside, all of the paint options are the same price. When I bought my Golf, a decade ago, pearlescent finishes (like Daytona) were more expensive than metallics which, in turn, were more expensive than plain colours. Does anyone know how they now all cost the same? And are metallics and pearlescent paints still more expensive when they need to be touched up / repaired?