Ok, so I'm rewatching H2O and I think I now know why I have so much of an issue with Mako Mermaids (apart from the obvious... acting). The watchers can relate so much more to the H2O girls than they can the Mako ones. These are humans who have a weird change thrust upon them. We can more easily put ourselves in their shoes making us more comfortable with the characters and fulfilling any fantasy element we wish our own lives had. The Mako girls, however, are weird and foreign because they ARE mermaids trying to adjust to the human world. The think things like cats are weird and it's a lot harder and less interesting for us to take step back from our own feelings and say "yeah cats are weird." It's a lot easier and more fun to imagine ourselves as mermaids and thinking "how can I avoid the full moon." Anyway just my two cents.

As a side note, a canadian/USA mermaid? How the heck are they going to explain that one?