Unlike some of the other reviews I've read, our hippo gobbles pretty well. Not only does he gobble blocks, but I've seen other objects pop up into his belly.
That said, this is by far one of my daughter's favorite toys. I bought it for her when she was around 9 or 10 months old. We have other Peek-a-Blocks at home which she really enjoys, so I figured that if she wasn't really into the hippo, she'd at least have new blocks. Well, it turns out she LOVES the hippo, and plays with it daily. It's given her so much confidence and has probalby been strengthening her muscles - all of them, since she not only walks with the hippo, but swings it around as well! Hey, it's got to be durable if it can stand that much abuse.
We haven't tried the ride-on conversion as of yet, but as far as I can tell, she enjoys playing with the blocks and she's delighted for being so mobile.
All in all, I'd consider this toy a pretty good value for the money. At less than $25, you get a walker, a ride on AND a set of blocks. Not bad in my book.