If you have been using cheap orbital sanders, the Fein will be a big improvement.  For about four years, I have been using the Festool 6" Rotex 150 but it goes through motor brushes about every year.  So, I thought a change was in order.  I bought the Fein sander hoping not only to solve the motor brush problem but maybe improve over the Festool.  There is absolutely no comparison.  The Festool is a far better sander.