OK, well its safe to say building codes, comfort expectations, technology, means of heating and cooling have changed and therefore yesterdays advice doesnt nessesarily apply to todays families. Besides we dont ned to hear the roosters, we have alarm clocks and get up later anyway.
Its really rather unfortunate this salesman was the one who came to your house. My guess was he's hungry, triying to manipulate stock, and can only sell on price so he offers the cheapest equipment he has.
Go with the 90+ and another contractor.
Now, I would look for a Ruud dealer and get the Mod 90, York may be releasing one soon, but the Ruud has been around and proven for 10 years, York will have to wrok out the bugs if and when they release theirs.