In my experience, converters don't really work very well and something always fries while using them. As has been said, laptops, phones, etc are all dual these days and no need to even flip a switch.

Most hotels have hairdryers so no need to pack one unless you have specialized hair needs since they're usually rather weak. You can find inexpensive Conair and Revlon curling irons that are dual voltage. For the past 25 years I've only bought dual-voltage appliances, so the only thing needed is a plug adapter. Sometimes you need to turn a dial from one voltage to the other but many appliances these days all you need to do is plug it in and it knows. Easier, safer, smaller, less to store and pack.