FWIW fixed splitters are not ideal if you have files that are partially modified as they don’t perform content-based splitting.
So if you have a large video file (say 10 GB) and add one byte somewhere at the beginning (for example by changing embedded text metadata), fixed splitter will need to reupload 10 GB. content-based splitters (buzhash and rabin karp) will detect the change and typically only need to upload one or two chunks (<10MB total).
Fixed splitter will be much faster, though.