Stack Inserters will wait FOREVER until they can pick up a full stack of input items before dropping them on the destination.
The best effort stack inserter will pick up as many as possible, then drop the stack on the output. This requires a decider combinator to override the stack size if we are holding a less then full stack.
https://factoriobin.com/post/kuva7t
I'm using this to compact up sushibelts with great impact!
Sure, collecting from its pretty close. However stacking ONTO a belt gives a 4x space multiplier, quadrupling the throughput of a belt.
That's true, I haven't been to gleba yet to unlock it. Had to get those sweet sweet em plants first.