So Darlyn on GTAForums wanted a mod that would trigger autosave manually, so I made a simple script to do just that.

How to install:
Make sure you have the latest version of GTA V.
Install latest Script Hook V by Alexander Blade (http://www.dev-c.com/gtav/scripthookv/).
Copy the "BetterQuickSave" and "BetterQuickSave.xml" files to your GTA V directory.

How to use:
Press the plus (+) buttton (the one right next to the backspace button) to trigger the autosave.

Customizations:
The key. Use this website to get the hex value for the key you want to use: http://msdn.microsoft.com/en-us/library/windows/desktop/dd375731(v=vs.85).aspx.

Notes:
The first time you press the button it will ask if you want to overwrite the existing autosave.

Credits:
Darlyn for requesting the script.
LetsPlayOrDy for creating the script.

Please do not redistribute without my permission.