Is a dedicated unit better than a combo air purifier/dehumidifier?

[SRJDIY]

Hi all. My question is pretty much what it sounds like - are combo units as good as dedicated purifiers or dehumidifiers, or are they mediocre at both tasks?

For context: I have a nasty combination of asthma and hayfever, so I'm planning to get an air purifier with a HEPA filter to remove pollen, dust etc. I already have a vacuum with a HEPA filter, but I can't realistically vacuum every day.

However, my house is also prone to damp and condensation - humidity usually hovers around 70-80% in winter. That can lead to mould spores, which are also bad for my breathing. Plus I tend to sweat like crazy in the summer, so less humidity sounds appealing. So now I'm wondering if it makes more sense to buy a combo dehumidifier & air purifier instead - something like the MeacoDry Arete One, for example.

What do you think? Any advice would be appreciated!