this is my final despicable forces full-game run
It is recommended to use an angle that goes directly to the IC if you haven't done that already. If you're too low/high when you're aiming at the IC, chances are, you could miss. Watch my 17:55 run as you'll know what to do after that as it'll be more consistent.
The game intends the ice creams to shoot every 0.25 seconds (240 BPM) assuming you hold the spacebar. With Suntech, it is roughly 0.235 seconds, which is equivalent to 255-256 BPM. That involves tapping the spacebar at that rate.
Try doing what sage recommends you to use (254), then 256 until you hit 260 if you're consistently getting under a 5:28 sun. And try to use a metronome (if you aren't already) which will help you improve your sun quicker.
just learn ultra invis...please (edit: let's see how it'll go)
Congratulations, you've tied my PB.