Agreed - the Nurse is a really very bad choice. Smooth hounds and bullhead sharks(Horn & PJs) are much better choices.
Especially for anyone that doesn't know much about keeping sharks. And have to room and funds to set up a large swimming pool size lagoon for the adult Nurse.
While Nurses tend to be an incredible hardy species. They can also be quite piggish in captivity.
In the Wild, juvenile Nurses may average only about 4-6" per year, and take up to 15-20 years to reach maturity at about 7-7.5 feet long. But in captivity - inexperienced keepers tend to over feed sharks, especially juvenile Nurses. This means they usually grow faster(sometimes much faster) than they normally would in the wild. And in the case of a nurse, it can mean that they may grow more than 4 times their normal rate (up to 2" per month).