There's also Pool Boss, but each have their own weaknesses and strengths. Pooly is a bit stingy with Playmaker actions, and some of them aren't implemented well. For example, all of the actions miss "use owner" for despawning and spawning, so you have to get owner which is an action more in the state. Then there's "no other game object selected" warning when you are using referenced game object for the spawn point. There's no warning only if you drag and drop the object into that box, which is silly, and so on. Lastly, but not least important, is tht support is a bit wonky and sometimes you need to wait days for an answer from the dev, if you're lucky.
On the other side is Pool Boss, which has great actions, great support and overall works like a clock, BUT, it misses an important feature that Pooly has, and i'm quite astonished why something like that hasn't been impemented. You can have separate pools which are not filled until activated, which means you can have pooled items in different pools for first and second level, but you activate the second level pool when you get to the second level, thus improving loading and compiling times a lot. You can manually add items to the pool from array to achieve something similar but its nonsense. That's the situation, so choose wisely.
I hope Playmaker will address all those things, since Pooler actions are really too simple to be of much use for some advanced usage.