I've got close to 400 dives on two canon housings, with zero moisture (not even condensation). A friend had about a dozen dives on a Nauticam that began leaking at shallow depths. Luckily, he noticed (thanks to the sensor) before losing the camera, and Nauticam admitted it was a manufacturing issue. They replaced his housing with a shiny new one, and he's been good ever since.
So in my experience, the Nauticams have a higher failure rate, but I'd feel comfortable with either brand. Most floods are the fault of the diver, or of someone handling the diver's cam improperly, but it's a crap-shoot if you get a bum housing, and they can come from anywhere.