

I bought AE cooling-gel ear cushions for my QC Ultra 2nd Gen. They don't change the sound much but do change the ANC a bit. Here's my observations. (pic2 for comparison)
I've been using the Bose QuietComfort Ultra 2nd Gen for 2 weeks daily now, and I have noticed that my ears get sweaty because of the seal of the OEM ear pads.
These earpads from AE are partly made of p-leather and partly made of fabric; the latter is what touches your skin. One of the reasons for buying these pads was also the PFAS scare from a month ago. But I don't worry too much about it.
These cushions are a bit deeper than the OEM ones, which adds a certain level of comfort. Though they increase the profile of the headphones while they're on your head as well. The cooling effect is immediately noticeable, and the fabric feels soft to the touch on your skin around your ears. I've been using these only for a day now, so I can't say much about the long-term use yet, but I will keep this updated.
Sound quality-wise, it stays pretty much the same. My ear isn't trained to tell the difference.
ANC does change a bit, I feel like. I have to do some more tests, but for now it seems like it lets through the mid and high frequencies but does cancel the low frequencies better (kitchen noises came through, while air ventilation was pretty much gone). The OEM I noticed had issues with the air ventilation, but it dampens the sound of talking and the coffee bean grinder pretty well.
The weight also increased because of the cooling gel, which is noticeable.
Overall, I will keep using these to see how I like them in the long term and keep updates here. For now, I have mixed feelings about them. I am also still looking for velour earpads, actually.