Frank, you probably know this, but, all humidifiers come with a cost. I personally like ultrasonic, IF, you can get pure water. I have an RO system. warm mist and cold mist all require evapoator cleaning and the wick type require wick replacement. I use two wick type in my home to keep the humidity at 40%, but have to replace both wicks about every 3 weeks during the heating season. They're $9 each!! But I go through about 18 gallons of water per day. Which means several fillings per day also. 2600sq ft house. If you have a forced hot air system you can put in an auto system if you also have a water supply. There is a good one that uses many disks like cd's to create a large wet surface area for the air to blow across. They claim it doesn't care how hard the water is. The drum style will also clog the drum with hard water or even the salt used to soften water. And those are really whole house, not room sized. So I guess I recommend lots of plants and a pond with waterfall

I have a kenmore and an emerson stand alone units, under $100, look identical, one rated at 1800sg ft the other 2700. Same size, same fan size, same wick size. But on low speed they do the job. You would not want to use them at high fan speed, they're not guiet.
I think thats was my 3 cents, but i hope it helps some.
Mike