I recently switched from a Windows Phone(Lumia 950XL) to Android(Leeco Le 2) mostly due to lack of apps, and i tried this game since everybody talks about it, god it's really well made, a sort of tower defence but pretty fast and fan to play, i usually don't like this genre of games, though i really got into this one immediatly, i didn't expect it to be so good, great gameplay with quick but also tactical battles, cards collection and upgrading system, clans etc everything has been designed well, now i'm playing it regularly.
So about the topic, when i'm full on chests i rather wait for them to unlock and then play, though from time to time i play even if i'm full, you'll always gain coins and trophies so it's still worth it, and loosing doesn't really cost you that much after all, also i really enjoy the battles themseves besides the rewards