"Whisper Quiet" or "Dual-Ducted" Air Conditioning - reviews?

One thing to watch on the ducted returns, where they meet under the AC unit, our manufacturer installed a foam type insert in the truss to separate the supply and return, and some have shifted causing a breach between the two. This really reduces efficiency and you can actually feel supply air coming from the nearest returns. Aluminum tape cures the issue - you have to access from the top by removing the cowling.