Pros: Sturdy, Grows With Child, Worth the Money
My son received the Fisher Price Rock, Roll n Ride Trike for Christmas in 2005 when he was 1.5 years old. He is now 4 and he still uses it daily. The bike can be used as a rocker, a bike with a handle that can be used to push the child, or as a regular bike that your child can peddle on his own.
We never had the chance to use it as a rocker, he went straight to riding the bike (sitting and pushing it with his feet) when he got it. I would say that a child as young as 9 months would get use out of this item. And I can see my son using it until at least age 6. This will be an item I keep around for a long time.
My son, and the neighbor's children (4 and 6), play on this bike every day that they are outside. It has been one of the best gifts he has received!
I definitely recommend it! It is well worth the money. And to let you know how durable it is - I ran over the bike and bent the peddles a bit last year, but the bike is still going!