iClarified:

A new video confirms previous reports that the 32GB iPhone 7 has 8X slower write speeds than the 128GB and 256GB models.

Unbox Therapy demonstrates a benchmark and real world test of write speeds on a 32GB and 256GB iPhone 7. The benchmark found that the 256GB model was able to write data at 341 MB/s; whereas, the 32GB was only able to write data at 42 MB/s.

The video is embedded below. Feel free to skip to 1:14 in, where the side-by-side test between the 32GB and 256GB iPhone 7’s starts.

Is this a big deal? I’d say, it’s worth keeping in mind if you are on the fence between the 32GB and 128GB iPhone 7.

UPDATE: Turns out this is standard for SSDs. Larger SSDs are faster because of parallel design. Here’s a link to a site that explains this pretty well (H/T Rob Pickering and Robert Davey).