Just like any other country in Central America, you never know what might happen. I have travel Guatemala from north to south, and east to west. Melchor is a nice town, the market has lot to offer and relatively cheap. Just make sure like we say in our country "don't give your self color" that means don't wear too much jewlery, don't flash money around, stay low key, and treat the locals with respect... and they them selves will look after you.