something to consider, on helmet reviews on fogging or not,
a TON of how well a helmet shield stays fog free also has a TON to do with the physical condition of the user, folks in SHAPE as to folks maybe NOT so much, will breath a LOT differently in like conditions
so when asking, you also need to ask and be honest about your physical condition , are you a rather active person with good cardio or not??
ME< between having only 1 lung, asthma , and other breathing issue, and will honestly say NOT in the shape I once was,
I can fog a helmet THINKING about riding a snowmobile ! LOL
SO< like I said, condition of user matters a lot IMO< and is something many leave out of reviews, or maybe don;'t even consider when talking about how they like THERE helmet!
now that being said
I had a castle CX 950 with heated shield, and the heated shield kept thing fog free for me, what I can say on it is, the shield worked GREAT when plugged in for me, in temps from minus 20 on up(had a day of some major cold temps and still rode in it) rode in a sleet rain mix, and will say it did MELT the ice build up, but at times it needed help to swipe it off shield
things I disliked, were first I wasn't a big fan of the latch to open the face part up, what I found is after riding a lot in snow dust from riders in front of me, or , just maybe due to me breathing a lot more than many, condensation and snow would build up on the latch part and at times, would even Stop the helmet from closing latching on the latch if you were able to open it, as ICE would also cover the mechanism,!
it wasn't a problem to say I HATED it or wouldn;t buy again, but was a issue I had many times over the two yrs I used it!
NEXT was the slide down orange screen, I never liked that color for a shield lens, and I dis liked how that shield would rattle, found the rattling annoying after a while
other things I found, is this helmet ran two sizes smaller than other helmets I had to get the same fit, it is a little on the heavy side too, but not enough to not buy again!
I also had issue's with shield plug coming out, a simple zip tie to things solved that,
over all I say a good helmet, over priced for what it is, but what's not over priced anymore!