Well, sort of. The 6" runs lead to floor vents that are very large -- smaller ones are 8x10, larger are 12x14. Immediately after the install, I had terrible stratification, somewhere around 5 - 8 degree difference between floor level and the 6 foot mark. (All ceilings are 9 feet.) Feet were freezing, head was warm lol. This is a 100 year old house, and the floor vents are basically built in and "framed" by the hardwood floor, so reducing the size is not an option. We blocked off roughly half the surface area of them from the underside, and it was a huge improvement, there is now about a 2 degree difference. (Is that reasonable?) They are the decorative type old Victorian grilles, so they really do nothing for the throw either. Oh -- and all returns are also at floor level, in the baseboards.As far as good air mix. They didn't mislead you, its probably blowing out fast at most if not all registers. Which does give a good air mix.
Just it can be loud, and use more electric then need be.
If they were to increase the size of some of the 6" runs, thereby reducing velocity, would I likely be getting back into stratification problems? Or should they be able to overcome that? I can live with the sound, if I'm going to be more comfortable. It's still WAY quieter than my old unit!!
Thanks again for all the help!!!