To use the Pi as a full desktop computer, even with the latest model 3, is a nightmare. To begin with, it operates Linux, which has a steep hill to climb and is not recommended for beginners. Linux zealots believe that this year will be the year when Linux finally makes it to the desktop of the average user, but it never has and never will. Even with the new model's performance improvement, you'll still struggle to do routine chores. The minuscule delay between pressing a key and seeing it show on the screen will ultimately get to you.