Always go down (er, hum) further than the advertised comfort range if you're taking a 'lady' with you and it's -3. Mine uses both four season sleeping bags -whilst I make do with whatevers left, lol - especially if you're an old fart like me - comfort zone ratings are generally rubbish gauges of comfort.
Two problems with those points. One, you only get one or two nights for your £179, this sleeping bag could last thousands. Two, one of the main reasons it's expensive is because it performs exceptionally well in the cold weather, at 0 degrees you will be perfectly comfortable. And I love a nice hotel holiday every now and then, but it's not any better than home, and nothing comes close to this:
But for £179 I could sleep in a nice warm hotel room, out of the cold.
It's not just sleeping bags, it's anything that people vote cold when they don't have the knowledge to understand the price tag. Perhaps they think they understand enough, after all "it's just a sleeping bag". It's somewhat worrying to think that people assume any sleeping bag will do, exasperated when they see every premium sleeping bag deal voted cold. A considerable number of people die every year because they have the wrong equipment for the activity, nothing is more important in the winter than your sleeping bag. Not to mention all the other benefits from life time, weight, pack size, etc.