Are there good 6DOF or 9DOF IMU boards? What about 9 Degrees of Freedom - MPU-9150 Breakout board from Sparkfun which sells for $50?
That is a combination of a MPU-6050 and a magnetometer in one chip.
So it is very small and it is a good sensor.
The Sparkfun link to the code is a copy of Jeff Rowberg his code.
I think it is better to use the code from Jeff Rowberg himself, MPU-9150 9-axis accelerometer/gyroscope/magnetometer | I2C Device Library
But if you buy a MPU-6050 board on Ebay, with a HMC5883L board, you have also 9DOF for less than 10 dollars/euros with the same accuracy.
The problem with using 2 separate devices, is that you cannot take full advantage of the capability of the
MPU device. Unless someone has figured out how to do it.
You can “correct” the orientation error of the MPU device using the magnetic field, but difficult to feed that
corrected value back into the model so that it stays correct.
Not sure what your criteria for 'good' are but I purchased something like this from eBay for about $20 and it works okay. All the chips are digital and use TWI to interface to arduino so only 2 pins needed (apart from power/ground)