In reply to FreeloaderJoe:
I've had a Minim 400 for many years. It's rated to -5C 'operating' temp but I found that was really the lower limit and even slightly beyond that I was cold. It has no neck baffle, which I don't mind, but I don't remember an issue with the hood. I was always a warm sleeper, slightly less so as I've got older. I've always used relatively thin mats though, compared to what I see some using.
In more recent years I've used a Pipedream 600, which has a 'limit' of -12C, which is about right - maybe -10C?