Pardon for lately reply.
Kindly see the following link for additional reference.
https://theairtacticalassaultgroup.com/forum/showthread.php?t=28730
Just an FYI. the IMU with GD20H+M303D had been discontinued by Pololu.
You can still purchase it from offshore retailer (China).
Its work great.
//#define GD20HM303D_6a // GD20H + M303D at address 0x6a
//#define GD20HM303D_6b // GD20H + M303D at address 0x6b
The MPU9250 is ok (Didn't test extensively)
I wouldn't recommended purchase the below component. Too much noise and drifting
//#define LSM9DS0_6a // LSM9DS0 at address 0x6a
//#define LSM9DS0_6b // LSM9DS0 at address 0x6b
Regards
Ki714