First all let me start by saying Hi from a newbie. Just moved in to a newly built 3100sqft single floor slab construction brick house in Oklahoma. The house has 2 furnaces in the attic. I would like to have a whole house humidifier as I have really dry skin and the winter is a killer for my skin. I had a Honeywell Tru Steam in my old house which was 1600sqft house and the furnace was in the garage leading into the attic and never really had a problem with freezing. I was considering going with the Aprilaire 700 with Honeywell IAQ to be able to run the humidifier even if there isn't a call for heat. Questions I have are as follows and I want to thank you in advance for any help you could provide.

1. I know having humidifiers in the attic is not a great idea but not sure what other choice I really have. Looking for opinions and possible options. If I do install them in the attic I will insulate the water lines very well.

2. Would I benefit from installing 2 humidifiers (one on each furnace) or would one suffice.

3. What would I benefit from the most a flow through or true steam.

Thanks Again
Scott