The Cool Space 350 is a huge upgrade from the 300 and well worth the extra money, especially when it comes to volume of water and fan cfms.

This unit has kept the 520 sq ft section of the house between 69 and 72 consistently.

The oscillating feature works well and spreads a cool/cold breeze over a pretty large area, something that a stationary fan can't do.

It really does cool you off on any of the settings and the charge lasts me all day and I use it ALL DAY(and sometimes at night).