Just FYI on Internal Release (and infuriate) 60s vs 90s.

There is no reason to use them on CD.

All other things being equal, using them during zerk is a 50% increase in effectiveness.

In 3 minutes, 3 60s cd is equivalent to 2 90s CD * 1.5.

So it is a wash on paper. In reality, it may also sync better with other CDs and/or burst windows, if you are saving zerk for that.

So go ahead and save them.