I'm trying to improve my sun and i've been told to use a metronome.

Sage tells me to use 254 BPM

Ringo tells me to use 256 BPM

someone else (I forgor who they were) told me to us 250 BPM

I just wanted to know what is the correct BPM to use. Also any additional tips to get a faster sun would be appreciated!

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.

@Ringo6575 I meant like what is the exact perfect intervals for BPM on a metronome for suntech. like what would be the ideal BPM to do the Sentech assuming i did it perfectly. (How long does it take until you can shoot another ice cream)

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.