I almost don't want to use any Magic Orbs now with all of these reports of 4*, but then, it will likely never be fixed so they'll just remain there. :/
Seeing Reddit, a lot of people are posting bad pulls [some going as much as 40] without a single 5*. I don't understand how they expect this game to keep going, with the slow rate of earning free Magic Orbs, the high cost of purchasing them, and the horrible rates in the Gatcha. Sure, the best monsters are often obtained outside of the Gatcha, but how will you get to that point if the Gatcha never gives you anything interesting?
Honestly, with as many IAP games are there are Puzzle & Dragons, Brave Frontier, School Idol Festival, Terra Battle, etc., it's not as though there aren't alternatives. Of course the actual gameplay portion of Monster Strike is a lot of fun, but it's a shame that it's nearly crippled by the RNG of the Gatcha.
[I still haven't used my Magic Orbs, and I still might not. We'll see.]