Every mother I've seen with a cup seems to have the Tommee Tippee ones - they're a good size, not too tall - and I've been using them too from the last bottle (can't remember when that was, some time around a year?) to 18 months. She seems fine with the Avent magic cup, which is a non spill one, but prefers the TT, and the TT are just a better size. I have tried the Doidy, because I think water tastes HORRIBLE from plastic cups, and when I've carefully given her real water from a real glass, she goes a bit crazy and says 'nice! nice!' and drinks tons of it, so I thought I'd try to move on to the next stage. But she just poured the Doidy all down herself and didn't catch a drop. Everything soaked.