If I have to choose I will take the dry box. I have always been very much on the flip-flop fence about dry cabinets. Maybe that is why I have never actually bought one in the last 2 decades. I don't buy more lens then I need (I have 3 lens after selling all others I have no need and only keep one body) thus I am always using my equipment and they tend to follow me and when it is not, it is in my room in my dry box which is loose closed heh..or I just place them about my air-con room. And since I always make it a point to send my lens in for cleaning once every 2 yrs or less... . So between using them and the time I get them serviced, fungus is not a problem with me. Services is someting I feel everyone should do once in a while with their equiment. It is an investment that pays you back in lots and lots of faithful usage in the years to come.
The only time I had a fungus attack with a DX lens (18-70m) was when I use the rubber buld blower and blasted so much air into the back of the lens that it blew the light oil from the gearing parts onto the front element's on the inside of the lens!!!. I let it go for a few weeks since I had no time to sent it in as I just bought the lens...but this light oil started to turn into fungus. I guess spores got caught in the oil and help it get a foot hold on my glass element and it start to spread abit. Any way....got it clean and that's that lah. I hardly get any fungus on my camera or lens and without a dry cabinet. Some have a fear factor about their priceless investment, some just ahve a security blanket mentality about it which is fine, to each their own and some.... well maybe too many horror stories they read but for me, a dry box was all I ever needed and have bought ( and throw) a few over the years and just use silicon and dry cloth to keep moisture at bay at least long enough till the next time I take my gear out again to shoot. Which is every other day or so as it is part of my work at the office.
If you have a tendency to leave your gears untouched for weeks or months or you have numerous lens and bodies that you can't use all at once then I think you really need a cabinet to minimise fungus and mositure that could damages internal parts, seals, LCD screen and their electronic circuitries and micro gears. These days fungus are not your only problem. Look at the bigger picture and you will find alot to worry about or over worry. If it makes you sleep better then check out all the safety precaution you need to buy to keep your equipment in good order.