How big is your home? What BTU was quoted to you on both brands?
I'd go with the Mod, hands down.. They are the best equipement out there, and no one else in the forced air can match the comfort.
You can down load a home owner's version of the loac calc (red tab on top of screen) for $50.
With the mod running steady and slow, it will help with your basement set up.
I would put a mod in my home if there was a Rheem/Ruud dealer in my area. so I went with a Trane XV90 instead.