I successfully washed clothes in Italy and had them drip dry overnight.  I was warned they might not dry due to the limited hotel ventilation, but the hanger allows the front to be separated from the back of the garment, allowing airflow.  They pack down very small, so they're worth bringing.  I also bought the model which is a simple triangle, because it was cheaper, but I used these more.  They're worth the slightly more money you pay for them.