Bad tasting grilled food is not due to what's burning (whether it be charcoal, propane or NG). It's usually due to who's burning it.

Cheap gas grills just don't get hot enough for proper grilling because the burners are poorly designed and/or the fuel/air mixture (venturi adjustment) is all wrong. Charcoal is simpler to get right because it'll burn the same whether it's in a rusty bucket or a high end grill.

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