The only thing that one needs to pay attention to is the sizing. It is common practice for latin dancers that the sandals should be very tight and the toes should touch the floor, meaning there should be no extra room at the front of the shoe. Most manufacturers allow half a cm extra room in the front. Knowing this, I ordered one size smaller than the recommended sizing and the shoes are exactly as they should be. To be specific, my foot measures 24 cm, and I ordered a 37 which is listed as 23.5 length.
Regarding width, my feet are very narrow, so naturally the shoe is a bit wide for me, but I knew this before I purchased them. For everyday practice, I use additional laces to make the shoe really tight and stable. I would suggest to Light in the Box to offer shoes for narrow feet as well, because this would provide an excellent service to all of us whose feet are very narrow and have a problem finding the right shoes.