I own these three Maybelline VolumExpress Mascara's for different reasons and they're all three good for different things so i figured i would compare them for you.
One By One
This mascara is best for lengthening and seperating lashes to make them appear longer. It doesnt give any fullness or thickness but it defintiley lengthens well. Rounded wand.
This is the thickest of all three mascara's and the only waterproof one. It makes lashes super volumized and thick and definitely gives that false lash appearance. However - its very hard to remove so i suggest getting the non-waterproof version. Curved wand.
This mascara is supposed to give you 7x more fullness and length but it doesnt - it isnt terrible but it works as a regular mascara for me. Lengthens and volumizes O.K.. Straight traditional wand.
Out of the three the One By One is my favorite but i like to sometimes add The Turbo ontop of it to add more volume. They're each $5-$7 in drugstores.