We bought this when our 5 year old was 1 and she LOVED it. Purchased from a local toyshop so we were able to trial it first and thought that she'd love the flapping feet...which she did. Push alongs are great fun especially when first walking (and onwards), pull alongs better later on I'd say I think this is because push alongs have a fixed handle and of course because you can see it whilst you're walking. She also had a ladybird push along, the type with beads that twirl which she enjoyed playing with too but the flappy feet penguin was definately the favourite.
Unfortunately I vaccuumed too near the penguin one day and destroyed a foot... now looking for a replacement for soon to be 1 year old son.