I dunno man, I have both and I prefer the fleece. Warmer, softer, and doesn’t have the annoying ‘swish’ sound when you walk.
I think it all depends on the environment. On a chilly morning, the fleece is nice and toasty, but on a windy cold day, the Massif cuts the wind better and is warmer. The Massif also lasts a couple minutes longer in the rain than the fleece does if you end up getting caught in it. Obviously neither work as well as the Gore-tex part of the kit.
For a "regular" style of jacket, I always found the winter-weight Nomex jacket to be the warmest and most resilient in cold wind. I would always wear that when walking across the NSE flight line when the cold fronts would come through and the wind chill would be below freezing.