Just bought a brand new Arctic Spa Yukon 2 weeks ago. Lost power for 5 days in a row due to the ice storm that crippled Eastern Ontario/Ottawa area. When power was restored we opened up the tub to see the temperature....76 degrees! Unreal. We bought this tub on a neighbours recommendation because of the insulation and how they can handle the elements. Needless to say it passed its first test with flying colours. In addition it has been an amazing tub. Very comfortable with several different seating options. We are using the AquaFinesse product and it is working very well. Water levels are good, water is clear, and we smell just fine after getting out.
Also I want to mention the Arctic Spa Durham team for excellent delivery, service, and follow-up. During this "crisis" we did contact them and got their recommendations. They have been A1 and I recommend buying from them if you are going to get an Arctic.