I just bought and had installed by a licensed contractor a Honeywell TrueSteam HM506A.
Think its a 6 gallon whioch may not be enough for a 3,000 sq ft house. But its working fine except for one very important aspect. In the 5 days we've had it the fresh water feed into the unit, its a thin pipe through a small connector keeps leaking furiously to the point where the garage fllods. The contractor has been back and tried to fix it. We get it working and cycling OK then all of a sudden it bursts a leak.
The connector design looks very unreliable to me.