What is the difference between Arweave and Storj?

Could you please explain the fundamental differences between Arweave and Storj? I'm particularly interested in their approaches to data storage, security measures, and cost-efficiency. How do they differ in terms of scalability and ease of use for developers? Also, could you compare their market positions and the communities surrounding these two projects? I'm trying to understand which one might be a better fit for my storage needs.