I don't know who I want to unlock. I've always wanted ez but mal seems pretty cool too, and i've been wanting to play him.
Ezreal is a way better hero. Malzahar is pretty fun, but Ezreal is plainly better.
That being said, I would choose Mal, just because Ezreal is so overplayed and IMO Malzahar is pretty fun.
Ezreal's passive is also supremely useful, while Malzahar's is the exact opposite half the time.
Sorry, this is totally up to you.
I have no clue how you normally play or what types of heroes you like.
Ezreal is more geared towards support and short burst. Mal is a ranged controller.
© 2013 Riot Games, Inc. All rights reserved. Riot Games, League of Legends and PvP.net are trademarks, services marks, or registered trademarks of Riot Games, Inc.