Did you try doing a sizeof(My-UObject-Subclass)? I don’t feel like checking myself but it shouldn’t take too much time. I’d be a lot more concerned about performance if you’re going to spawning a whole ton. You know, things like will there be a huge spike if I spawn a hundred in a single frame? Do I need to spread the allocations over multiple frames? Am I making a multiplayer game (If so, I’d be concerned bout network replication as well)