We didn't have any problems with the Easy-Ups at all; dd used them all the time from about 15 months until she was dry just before 3, and used them at nighttime until she was 4 (she's a heavy wetter overnight). I guess it depends on the size and shape of your child (although dd is a skinny-minnie, so I wonder why they didn't fall off her, too!).
Go for small packs to start with, biglips, and see how you get on with each one.