FWIW. If the resistances & applied voltages are the same, then the current thru each will be the same. A larger mass will take longer to heat and will consume more 'power' (W = E x I), than the lower mass heater, ie; to reach the same temperature, but the lower mass heater will not use less current. Not possible..... (refer to Ohms Law).......
L.
ps. The higher mass heater will retain it's temp for longer than the lower mass one, & so will stop the dew from forming for longer. It will also be more efficient in overall power consumption over a longer time period.
pps. Use a PWM control....