Another thing that needs to be taken into consideration is how popular a piece of content is. If a piece of content is extremely popular it’ll have chunks stored all over the the SAFE Network and make it extremely quick to access. If it’s just a file that is only being accessed by one or two people it’ll not have chunks of it stored all of the network thereby reducing the speeds.
I know that doesn’t answer the question, but here is one recent topic for a possible glimpse of what’ll come with speeds - Benchmarking Testnets
If you search around the forum I do believe there are some other topics with some more numbers. If I come across anymore I’ll update this response.