Discussing "length of recording" option- any case for one over the other?

[Triggerfish]

Just curious what the proper setting is for "length of video" that is best for the memory card, downloading, and overall the "go to". I am tossed up on this because one thing effects the other- longer video length gives bigger downloads when needed, but solves my problem that I've had too many incidents happen at the end or beginning of a file. I've also been told, right or wrong, that the life of a card will be greater if you write less files, IE, set it to 3 minutes instead of 1. Or perhaps a good compromise is 2 minutes.. not sure.

thoughts on this?

I'm using VIOFO A329's and Blackvue Elite 9 (and other cameras for side coverage, etc.).

Thanks!