It definitely works. What I would say is having recently been wearing it a lot as I'm working full time on our place doing dusty stuff is that the straps are too thin and get uncomfortable after a while, so I want to get one that works as well but has wider straps.
The one I use is 7502, with the cartridge filters.
I never really wear it for that long so i cant say ive noticed it personally, but then again masks are never that comfy unless you wear the full one over the face.
Same here, this one:
https://www.screwfix.com/p/3m-4251-one-size-half-mask-respirator-a1-p2/464hy
It definitely works. What I would say is having recently been wearing it a lot as I'm working full time on our place doing dusty stuff is that the straps are too thin and get uncomfortable after a while, so I want to get one that works as well but has wider straps.