Does anyone have experience with - idk what they should be called - "single unit" diffusers?

Hi everybody! It looks pretty dead in here from the age of the most recent posts, which makes me sad because this was such a healthy, useful community on Reddit (good riddance), so I'm guessing I won't get any responses. But hey, you gotta be the change you want to see, so here goes:

I'm talking about the type of hair dryer that has a diffuser built into it so it can only be used for diffusing, not any other type of hairdrying. They seem to just be called "diffusers" so it's hard to search for them, but I've seen one from BedHead, this very similar item from Revlon, and this different (more expensive, but from the looks of it possibly better designed?) style from Bellisima Italia.

Has anyone used one of these? How do they compare to the attachment types? I've currently got a refurb Shark, which I'm pretty happy with, but it's big (hard to pack/store) and heavy and occasionally I manage to knock the diffuser off the end even with the magnets, because I am horribly clumsy. I never use a dryer without a diffuser, so I thought "Hey, why don't they make just a diffusing device? It would be lighter and smaller and no more struggling with keeping the diffuser on the nozzle!" And it turns out they do but I've never seen anyone talk about them so I figure there must be some hidden problem, right?