My son actually likes to use the straw cups, like Combi Step 3. He has now refused to drink from a bottle, thinking it is too slow. I started him on the straw cup when he was 7 months old. At first, he only drank water from it, but starting last month, he refused to drink milk from normal bottles, so we changed him to drink milk from the straw cup, and he loves it very much.
Alternatively, we have also tried Combi Step 4, which he likes, but cannot control yet.