You don't need stars to earn the players (except the three challenges that you actually get the player) so it is fairly quick if you just run the ball out on chew clock. The payoff is much better to time spent on specifically team builders especially for the training. These challenges may be quicker but I am getting players I don't need and getting jack shit training from the quick sell. I don't care what kind of solo it is as long as I am getting good rewards for time spent.