freeimu library mpu6050 +5883L

hi all
does anyone have any experience with the freeimu library?
i have a 6050 imu and 5883l mag and want to sensor fuse the best possible way. i also want to use the on chip dmp algorithms.

i know the freeimu is apparantly very good. the only thing is that the i2cdev 6050 library featured in freeimu is from back in 2011, and since then the on chip dmp has come along way.

so what im wondering is if i should just use the freeimu as is or should i just use the i2cdev library or should i try and bring the latest and greatest into freeimu myself, but very dodgeily.

also does anyone how to properly configure the stock standard freeimu library to use its 9dof sensor fusion algos even though im not using the official hardware. theres a bunch of commenting that needs to happen to do this sort of initial setup, but im never sure if it is using the mag or not. any way to test?

any advice on getting the absolute best performance out of these buggers with as few cpu cycles as possible would be much appreciated. probably just need roll pitch yaw because im only using it mouted on a wheeled robot.

cheers

Did you read this ?
http://playground.arduino.cc/Main/MPU-6050

I would recommend the Jeff Rowberg i2cdevlib library.
The FreeIMU library simplifies the calculations, so if you need those, you could switch to the FreeIMU libraries if you need them.