AH510/AH515 Original Connect Humidifier

I use this one currently https://www.venta-air.jp/products/#originalconnect I was impressed of the chemicals you can buy with it, all the residue is left in the water and a simple rinse will be enough maintenance. The ones that steam the air for example, there will be a ton of calcium buildup in the meshes that wick up the water to be heated up and evaporated. I've tried many, the piezoelectric ones (those that op talks about) are the worst.

Venta branded humidifiers are great

I went through this exact same obsession last winter when my bedroom was hitting like 18% humidity, felt like I was living in the sahara desert. Ended up going with a Venta after reading through probably 50 forum posts and I'm pretty happy with it - thing's been running daily for about 8 months now with zero issues. The maintainence is actually pretty minimal despite what some people say, just rinse the discs every couple weeks and change the water regularly. Only downside is it's not the fastest at humidifying but for your size room it should handle it fine, plus it's whisper quiet which was huge for me since I'm a light sleeper. The build quality feels solid too, like it could run for years without breaking down

I have one.  Haven’t needed service so no idea about the customer support.  I’m not sure the Venta formula cost is cheap enough to offset the cost for physical wicks, but otherwise it’s fine.

This is discussed often on here. Add the Venta to your list. Expensive initially but no paper filters to replace and it's fully cleanable, unlike any of the mist humidifiers that build up gunk where you can't get at it, seals disintegrate etc. protip: look into stearamine tablets for the paper or venta humidifier. WIth a monthly or so cleaning, and a half to full tablet added each cleaning, I don't get Any slime buildup ever. Cheap too.

Get an evaporative. Search on Amazon for "Steramine tablets". Put a half tablet in a 3gallon or less, a full in 4+ gallon tanks. Refill for a month or so, then clean it out, add another tablet when you dump it. The steramine will prevent mold/mildew very well. There IS a humidifier maker called "Venta" in germany, I got mine from Amazon, pretty expensive, but doesn't use the replaceable paper filters at all, uses plastic disks that rotate. More expensive at the start but I've not spent a cent on it in a few years now. Well, the steramine tablets, but I'm barely down a dozen out of the hundred that comes in the bottle. The paper ones of course you Do need to replace whenever they start looking waterlogged or gross, so keep that expense in mind. Still probably Cheaper over a decade than the Venta, but past that, well, the venta is still zero cost, and they Do sell replacement motors etc just in case.