I like it a lot. Sulani is really pretty and it adds a lot of gameplay for me. Like sending the family off to the beach now and then. The buy/build mode got some real nice stuff too, but I wish that they have added more objects though. The catalogue feels a bit bare bones to be honest. We got some real nice kitchen counters but no new fridge or stove? We got a Sulani themed bathtub/shower and sink but no toilet. What?
The mermaids are really great too. But I wish they were a bit more fleshed out like the vampires. I feel like there isn't a lot to do with them. They basically just swim around and that's it. I wish they could sit on land with their tail out. Like sitting on the edge of a pool or pier. I also wish there were some more danger to them. Like dying of dehydration. They only seem to get real tense if they're dehydrated. Vampires die from sunlight, why not make mermaids die from dehydration? It only makes sense to me. So yeah, they're really pretty, but that's all there's to them I think.
I guess my favorite part of the expansion pack is the world itself.