While I haven't used these products with cresties, I have used them in other enclosures.
I, personally, am not a big fan of the ultrasonic foggers. I am tempted to try one in conjunction with my waterfall in my new crestie cage, but in general I'm not impressed with them. If you are aiming solely to increase humidity, and have a glass tank, or something similar, you might like it better than I do. My enclosures have screen sides/lids/lots of ventilation, so it's kind of useless. Also, it doesn't create droplets on plants/cage walls for dew drinkers to lick.
I do however love the Habba Mist misting machine. I have 3 of them. I've used them with Panther Chameleons, Emerald Tree Boas, and Green Tree pythons. Beware that it doesn't create a fine mist, but more of a spray like a spray bottle. I love that you can set it to spray for different intervals of time, and at different intervals of time. Like you can set it to spray for 15 seconds, 30 seconds, 60 seconds, etc. And you can set it to go off every hour, every 3 hours, and so on. While I do wish that the reservoir was bigger, and that the extension nozzle was longer/more directable I do really love these.
22.214.171.124 Crested Geckos ~ 0.0.2 Gargoyle Geckos ~ 2.3.0 Columbian Boas (1 albino, 1 pastel, 2 aberrant, 1 rescue) ~ 0.3.0 Dogs (2 rescue) ~ 1.2.0 Cats (2 rescue) ~ 1.0.0 Extremely Patient Husband