Ronan insists that his LIKEaBIKE is a fast motorcycle. And who am I to argue? He's so joyful when he's riding it; he can even take corners without stopping.
It took him a while to get the confidence to really push off with both feet and glide, but now he's so fast that I have to run full-on to keep up with him. So I got myself a Xootr. Mommas deserve to go fast, too!
I think after riding this for a year, Ronan will be able to go straight to a regular two-wheeler -- no training wheels.
I know the LIKEaBIKE is pricey, so if you're looking for an alternative, there are knock-offs available (Skuut and the Kettler Sprint Bike are a couple I'm aware of). My only warning for any push bike is that your child needs to be able to have his/her feet flat on the floor to ride comfortably, especially at first. So pay attention to what the minimum height is. And put your running shoes on!
(And yes, we both wear helmets outside. Definitely a must.)