I've just bought one. It is great. Made by http://www.sunlightsaunas.com/
It was about $3500, and well worth the price. They are definitely not the same. The differences are listed here: http://www.sunlightsaunas.com/wi.htm
Optimus H-5210 Infrared Quartz Radiant
Heater, Electric Space
Heater, Efficient , Sunstar SG6 Infrared Radiant LP
Heater 60,000 BTU, Sunstar SG3 30,000 BTU Infrared Radiant LP Gas
Heater, Sunstar SG13 130,000BTU Infrared Radiant LP
Heater, Sunstar SG3 30,000 BTU Infrared Radiant Nat Gas
Heater, Sunstar SG6 Infrared Radiant Nat Gas
Heater 60,000 BTU, Sunstar 45K Natural Gas Radiant Infrared Tube Garage
Heater, Sunstar SG12 120,000BTU Infrared Radiant Nat Gas
Heater, Sunstar 45K LP Propane Radiant Infrared Tube Garage
Heater, Sunstar SG10 100K BTU Infrared Radiant Nat Gas
Heater, RE-VERBER-RAY LS20-40N INFRA RED RADIANT TUBE
HEATER 40,000 BTU , Sunstar SG10 100,000BTU Infrared Radiant LP Gas
Heater, DAYTON GAS INFRARED TUBE RADIANT
HEATER 161350, Mr.
Heater 22K LP Infrared Radiant Garage
Heater, ELECTRIC INFRARED RADIANT
HEATER GARAGE SHOP IN/OUTDO, ELECTRIC INFRARED RADIANT GARAGE OR SHOP HEATING SYSTEM, ELECTRIC INFRARED RADIANT GARAGE SHOP HEATING SYSTEM, ELECTRIC INFRARED RADIANT
HEATER GARAGE SHOP STAINLESS, Serengeti Radiant Infrared Tube Garage
Heater NG or LP, Bilux Infrared Radiant
Heater B600 House Home grage Workshop Basement Room Unit,