With MM & CSI's free shipping for orders $99+, I've never paid for shipping with either company, so I never count that $5.99. It's not hard to add another $50 of games & supplies to reach the minimum. If I can't right away, I use MM's hold feature and add more to the order later until it's $99+, then have them ship it for free.
But if you don't order much game stuff, ya, go for the Massdrop. I'll update the original post to reflect both types of buyers.