It’s a tricky one to answer, as temperature ratings are highly misleading and often abused by manufacturers, which is why we don’t give a simple number. They do not offer a fair comparison between two bags, and should definitely not be the single piece of data on which to base a decision.
We prefer to have a discussion to make sure a product designed primarily for the adventurous, travelling fast and ultra light, that packs down to a size of a longish toilet roll, is the bag for you.
So, firstly, if it’s for you, do you sleep hot or cold at home in bed?
Next, what sort of conditions are you hoping to use it? In the Mountain Raid 1.6 the 100g primaloft on the top side will loft (although not a fair term for synthetic insulation) to 1.6cm. This would be comparable to a thinner down that is bone dry in a lab, or thicker down that is a bit damp or has been packed and unpacked a few times. Down is better in low humidity, such as below freezing, but Primaloft can performs better in cool air with more humidity, and definitely performs better when wet.
And finally, the EN13537 temperature rating standard is described below. With which situation are you most concerned?
Upper Limit — the temperature at which a standard man can sleep without excessive perspiration. It is established with the hood and zippers open and with the arms outside of the bag.
Comfort — the temperature at which a standard woman can expect to sleep comfortably in a relaxed position.
Lower Limit — the temperature at which a standard man can sleep for eight hours in a curled position without waking.
Extreme — the minimum temperature at which a standard woman can remain for six hours without risk of death from hypothermia (though frostbite is still possible).