What can I say that hasn't already been said? Many of the family friendly Las Vegas attractions are also the most expensive. This is no exception. It was also really fun.
The facility is limited in size, which means taking it slow is the best way to go. Stop at each exhibit. Learn about the animals you are seeing. Ask the guides questions along the way. Instant gratification has become so ingrained in our cultural fabric that I feel like people are expecting rainbows and fireworks for 3 hours. They rush to the next "rush" as it were. If you take your time to walk the exhibit slowly and appreciate what is here you will enjoy your time and probably feel this is money well spent.
My favorite part of this exhibit (and my kid's favorite part) was the touch tank. If you can get over the docent reminding everyone of the one finger rule at least 3500 times while you are there (even when you are all only using one finger) you will love this. The animals are social and very fun. You can learn about and interact with creatures you may not normally get to interact with. I thought it was much cooler than the shark tank.
The sharks are cool as well, especially if you love sharks. In my deep down heart of hearts I kind of wanted to see some shark brutality, but they were all very well behaved and even downright polite (yeah, I just anthropomorphized sharks, get over it). I'd never admit that near the ocean though.
All in all this is a very fun family activity in Las Vegas and if you can afford it and take your time with each animal you will find it to be worth your time.