Take a look at Northstar Campers. Double pane windows, well insulated, cassette toilets and they will custom build (within reason) for your needs. We have an Igloo on an F350 and have camped in 0 and below without issue. We do have solar and two group 27 batteries that will carry us through the night with the furnace. Other than Cirrus I'm not aware of anyone else using the Alde system. Wish it came as an option for my rig but it isn't a deal breaker. Other cold weather rigs are Artic Fox, Northern Lite and Bigfoot. Probably others I haven't remembered.Only you can decide what is best for you so make it a point to go visit someone that can show you as many as possible. Good luck.
