While they are no longer my preferred grind, I still think a full hollow is the best to learn on. There are several ways a full hollow will be more helpful to a new comer.

1) Audio feedback. It sounds trivial, but when you use a full hollow you get excellent "popping" feedback. It helps you find the correct angle easily. Due to the thicker grind, a wedge or near wedge are just going to glide right over the skin and you won't "hear" if you are actually cutting anything.

2) More irritation if used incorrectly. This seems counter-intuitive but for me I could (and can still) feel it when I have a poor angle for the blade. I think a full hollow helps force one to use the very best angle.

3) Easier stropping. It's much easier for someone new to using a straight to find the correct way to strop. Like #1, it is because of the audio feedback. A full hollow will sing while being stropped and you will know if you have a correct pattern going or if the edge really isn't flat against the leather.

For those wanting to hone, full hollows are easier to learn on. It gets right back to #3 and stropping. It's just easier. Once a good technique is learned moving to a 1/2 or 1/4 hollow is a fantastic experience. Most of the blades I grab these days have that grind. Though I do still enjoy a nice vintage full hollow now and again.