I preferred hymnals until my vision started to fail. I still like to hold a hymnal in my hand and find the hymn in it and sing along but so many of the contemporary songs are not in the hymnal or are a different music than the ones in the hymnal which makes them hard to follow so I just hum.
I must say, I learned the basics of reading music by using a hymnal when I was a child. I learned harmony by listening to a woman in our congregation sing alto and following the notes in my hymnal. Now, singing harmony comes very easily to me.
Still, I don't think I'd want to go back to using hymnals all the time. We use them for our Wednesday morning Bible study, which is attended mostly by seniors. On Sundays, the hymn titles are in the bulletin, so people can look them up if they want to (I think the number is on the screen, too, in a smaller font), but I don't think anybody uses a hymnal.