GoPro Shako Mount stable enough?

Camera: HERO ($219.99)
Mount: Magnetic Swivel Clip ($34.99/$17.49)

To those who have used it, is the magnetic swivel clip stable enough when mounted onto the small visor of the shako? Is it really heavy or throws off your balance?

Additional Questions:
- Have any drum majors ever filmed a PoV with a go pro or something else similar?
- Would you recommend recording PoVs in general regardless of instrument (I play trombone), is it worth the hassle?

Thank you for your time!