Most of the time all I want are the ISOs. With Threshold 2's ability to accept Windows 7/8 keys make the in-place upgrade unnecessary, and superfluous. I really don't want the Media Creation Tool to put crap in C:\$WINDOWS.~BT and C:\$Windows.~WS even if I told it to just download the ISO.
The only benefit of using the creation tool is if I wanted to have an x86+x64 FAT ISO. Or Windows Update fails in a way which causes the upgrade to stop showing up, and one is forced to upgrade in-place.