Both are filed under “more than one person”, and buyers treat them as interchangeable until
they have bought a few. They are not.
A couple scene has a relationship in it
Two performers who work together regularly bring a rhythm that reads on camera: they anticipate each
other, there is less direction, and the pacing is steadier. If that is what you liked about a clip, look
for the pair rather than the act.
A group scene has logistics in it
Three or more people means camera position becomes a real constraint. Group clips tend to be longer,
tend to have more cuts, and tend to be shot in a fixed setup. That is not worse — it is a different
thing, and it is why runtime alone misleads here.
Who is behind the camera changes both
Some producers film themselves; some have a third person shooting. Self-shot scenes are closer in, with
fewer angles. If a clip felt oddly static or oddly intimate and you could not say why, that is usually it.
The practical shortcut
Find one pair you like and buy two of their clips before you branch out. Holding the cast constant is
the fastest way to learn what you actually respond to — far faster than working through a category list
from the top.