As a decent fan of Ninjala, I have to be honest.
The game play is fun if you know what you're doing, but prepare to be blindsided by the countless glitches and errors that occur every other minute in the game. People will suddenly become invincible after being hit weird, or an invisible explosion will knock you out. Not to mention almost every game you play, 8 people may go in but only 5 people may actually finish the round. It genuinely feels like the customization in the game was more refined than the actual game play. The emotes you can get are cute, though.
The matchmaking is also not the greatest. As a level 130+ I am constantly being matched with low level 7s in team battle, which ends up costing me matches. Most of the time, the game ends up disconnecting the lobby before all player slots are filled, which makes the wait to play a match really long.
Here are some positives: Based on the official Ninjala Twitter and YouTube channel, you can tell they take the game and feedback from players seriously. The game has plenty of bugs, but those bugs may eventually be removed after several updates. Be sure to submit feedback to the Ninjala Inquiry form.
The game itself is also charming. It doesn't take itself too seriously, which is the kind of game I like personally. The customization is nice, as we can choose our face shape, voices, hair, and clothing. The emotes we can use are well animated and bring a bunch of life and character into our avatars.
Get the game if you want a couple quick rounds of craziness, it's free. But if you want a long term, stable game that's fair and doesn't have too many glitches? Not the game for you. Maybe wait a couple months and see if there's been game fixing updates.