A "Salamander" or "Cheese Melter" grill is a type of infrared grill where the burner is above the food and cooks top down. It's able to provide a quick sear and in theory only apply the direct heat without any indirect heat. Unfortunately it lacks some qualities compared to a more traditional infrared grill.
First and most noticeably it provides 0 bar marks since there's nothing between the burner and the food, which instantly makes your food lose visual appeal and reduces some of the texturing effects.
Second, you lose out on the flavoring effects from the v-shaped grates and the burner's interplay. When the juices hit the burner they quickly evaporate and become flavor enhancing vapor and improve the taste of the food. The v-shaped grates also control the amount of juice that drips down below, preventing as much of the juice from leaving the food and dripping down below and making a more even and continuous flavor enhancing effect.
The 5 minute burn off performed after each grilling session eliminates the disadvantage of debris falling onto the burner, cleaning the burner with the high heat.
Finally there's the issue of price since these grills tend to be more expensive than our portable grills by a factor of at least 2. They require more material to make since the burner needs to be on top of a space and they tend to be much heavier and less portable despite needing to either be outside or under a vent.