I love my heat rope. It's the charm for heat in a closed chamber set-up because it's mounted outside the glass and warms the substrate releasing the humidity from the moisture contained in it, leaving the top layer dry.
Outside for my sulcata, I use an oil heater set on a thermostat. For my Russian, when it's cold I put him in a 3x3 two story terrarium with a 120 watt ceramic heat emitter. They last a long time! So do oil heaters.