Lense is hard to remove, too much foam, somewhat small
So I am a seat hog. I have a proto switch thermal but still had problems with fogging. While down at the local store I saw this mask and felt it was too good to be true. A thermal mask with a fan for under $70? So I bought it.
The fan is loud. It feels like a swarm of bees got loose in your mask...until I oiled it. I used a small pair of pliers and carefully pulled of the plastic fan (it is not glued) and placed one small drop of oil on the shaft. Then I put the fan back on. The result was amazing. The fan is now whisper quiet. I have sometimes had to hold the mask to my ear when its off my head to see if it's on.
On my head it now a small vibration only. Great product! (note I have no idea what doing this may do to whatever warranty you get).
After several months I had a problem with the on/off switch. I took it back to the store and had it fixed for free. I suspect the wiring in the fan itself is somewhat flimsy and being a hard core woodsballer I may have rattled it.
As for cleaning the lens this mask makes it very hard and is quite a pain. It can be done though and gets easier with practice.
As for fogging, when the fan is running you will not fog. I have gone through a swamp in the rain and did not fog.
The profile of this mask is very small. If you have a big head some bits may stick out, but I have never had a problem sp far.
The reason you buy this mask is for anti-fogging. It delivers. While there are many better thermal lens masks out there, if you want a fan you have to shell out more money. This is a great price for great anti-fog with a few reasonable compromises.
I have rated an 8. It would have scored higher except the fan should be quiter outta the box and the switch did break. Oh well. You maintain your marker, why not your mask/