Strong, reliable heating element (good wattage).A good nonstick / durable grill plate.Easy to remove & clean trays / plates.A lid that fits well (to trap steam).Venting or drip channels to channel condensation away.Safety features (overheat protection, auto shut off).Good customer support / parts availability.Transparent lid or view window (helpful to monitor).Stable base, proper insulation, safe handles.Clear instructions on layering (e.g. what to cook on top vs bottom