I somewhat disagree with those who say that the new Pro Deep model is significantly inferior to the old X3. I've used both models, particularly the X3 over the last year. I hired the X3 and found it did a fantastic job of cleaning the carpet, particularly vacuuming up water and leaving the carpet very dry after use. Easier to use, prompts you to fill up your water tank, while the X3 has you guessing or guessing when you'll run out of water. Both reservoirs are removable on the Pro Deep for easy cleaning and refilling. With the X3, the tank is more difficult to empty, and to empty the water tank either run the pump until it is empty or turn off the entire machine. Since both prices are relatively the same, I would choose the Pro Deep over the X3.