I too have a Sena Prism WiFi and it works very well except that the 3 minute 700MB files are a PITA to deal with when making a video to share or just go through an hours worth of riding (20 files!).
Now I get that this is probably a developer/designer's decision so not to much video time is stepped on when overwriting in loop mode. Non-looped or normal recording mode makes one big file per recording, so we know its possible for bigger files to be captured per session.
What Im asking for is a firmware (and software GUI) update that allows the user to choose the loop recording file size (time). Can be as easy as a feature or function option line in the same file where the loop mode is defined, yes?
At least make some selections like 3, 5, 10, 15, 30, 60, 90, 120 minute selections. Or make it smarter where it uses the user defined recording value, and when the drive gets to 90% capacity (or again user defined), just start making the smaller loop files, leaving the bigger files alone. Basically a hybrid of the normal and loop modes. So many things can be done instead of just a 3 minute bit bucket.