We've been vaporizing for over 8 years now, we have used many different vaporizers, some with fan, some without.
Fans have many benefits; they can inflate bags, they can make direct flow inhalation easier.
They also can make vapor less intense by adding extra air.
To us, we prefer the extra air, we find its easier to inhale vs a fanless unit. Not only does the fan help push the vapor towards us but it helps keep the intensity down a bit by adding air volume to the flow. Some people may consider that a con but with modern fan units being able to go down to ultra low fan settings, the extra air is more nice than an issue. The vapor may be a bit thinner but we find this easier to inhale.
If your goal is the thickest vapor possible, then you should look at a direct flow unit without any form of fan.
That or a bag based system with adjustable fan, allowing you to slow down the fan, increase the vapor thickness.
If you have dry throat issues, a fan based direct flow unit is maybe not a great choice. We'd either recommend using bag or if you do go direct flow, a fan less unit with water tool would be ideal.
We personally just have a glass of water near by and take sips as we go along.
Everyone has their own preferences, at vaporizers.ca, we are dedicated to finding the right vaporizer for you.