I'm sorry Q - what are you trying to infer from my comments. I said that I - as in me - "In over 50 years of camping with top of the range sleeping bags, both down and synthetic, they rarely came within 10degrees of their "official" rating" Yet the Wiggys - for me - meet or exceed their temp specs. And bear in mind that as I've gotten older, my resistance to the cold drops, so the earlier bags I used get an unforeseen "bonus" in the warmth stakes!
So it is a personal comparison on the accuracy of temp ratings. It is quite possible that what I find comfortable at -30C you would only find comfortable at -25C, true. (you being a weak and feeble woman and all
) Joke, folks, joke! However that doesn't invalidate my comments about the untrustworthiness of the temp ratings on other bags. It's a relative comparison.
It is also true that there are some weird definitions of what "Comfortable" means re the ratings. If you are made of metal, have an constant internal heat source, do not sweat or move whilst sleeping, have no internal vascular system that draws heat to the core and head as temps fall, then you can put some reliance on the EU EN ratings. And often you'll find winter bags (especially those designed for climbers) whose "rating" depends on you wearing full protective, insulated clothing as well as the bag.