Yup, a dry cabinet will adjust the humidity accordingly and prevents your camera lenses from getting fungus. As you know fungus will degrade the lens and it's costly to clean, so better to get a good dry cabinet. A 30L or 60L should be sufficient unless you have a lot of gears.
maybe someone can just setup a dry cabinet/dry box sticky on the newbie page (or there is already one). i seem to always see dry cabi/box questions here, and most of the time they are asking the same thing. no offend to anyone. just think that maybe a sticky on this topic can help the newbies find info more readily. any idea how to go about doing it?
if you are under budget constraint, a relatively cheap alternative is to get an air tight box, and put some silica gel in it. You need to change the silica gel regularly though, or fungus may start to grow.
A dry cabinet is actually similar to an air tight box, except it will automatically dry the cabinet if it detects that the humidity in the cabinet is higher than what you have set. Further, the dryer unit always automatically purge the moisture out of the cabinet unlike silica gel where the moisture is trapped in the silica.