It isn't the fastest coming back, however. Going out it's instant. I withdrew $700 from BetAtlas on Friday afternoon and as of yesterday (Tuesday) it still wasn't in my checking account. The weekend probably had something to do with it, but still.....
It is an easy was of getting money in and out of books. Most books only allow you to do small limits the first time, but once a few checks go through with no problem you can usually load up heavy using this method. Its also good for withdrawals because some books won't charge you any fees. Make sure you use you a legitamte email address when you sign up so you get notified everytime a check is processed.