I've been playing on Alpha Draft for about 2 weeks now and so far after an initial investment of $15, have been making money each week. Not an appreciable amount mind you as I messed up the first week and used the second week to make back what I had lost and initially invested. However, much like selling stuff on Diablo 3, small gains eventually lead to larger gains and as long as I am growing my funds each week, I'll be happy.
So far the experiment is working and I'm curious to see just how much I can make by the end of the summer. Might post my thoughts on how I pick a team later as I get more experienced with each game.