Don't know if it's the same in V5, but, in V4, you couldn't set a default duration. However, you CAN create a generated media event of any length you want by dragging a loop region in a video track, right clicking, and choose "Insert generated media". The media will be sized to your loop region, and the properties dialog will pop up so you can pick which preset you want.
Are you sure that works? My generated media always comes in at 10 seconds; still images come in at whatever duration is set by the preference you mentioned...
Ok, I get the duration specified by that menu option when I right-click and say "Insert generated/text media", but not when I just drag and drop from the Media Generators window - then it's always 10 secs. Do you get your default setting specified by your preferences when you drag and drop, too?
Ahh. I see. Different behaviors depending on how you do it.
To me, this is an issue. In an NTSC project I really don't like these 7/10ths frame things. I want it to be creating events that are whole frames in length.