navX Micro I2C voltage and Roborio

[cpapplefamily]

I been digging around the documentation. The navX is a 5v board and the RoboRIO Onboard I2C Interface is 3.3v http://pdocs.kauailabs.com/navx-micr...-installation/. The MXP-Expansion I2C ports seem to be 5vdc. Should I understand this to mean we should use the MXP-Expansion I2C interface?

reading on at the bottom of the page

Electrical Notes

The I2C bus standard requires that the SDA and SCL pins be pulled up with a pull-up resistor on each line. The RoboRIO internally pulls these lines high – but if connecting to a host computer without pullups, the SDA and SCL lines will need 1.5KOhm pullups.

The navX-Micro I2C pins are 5V tolerant, so the host computer can use either 5V or 3.3V DC levels on these pins.

I read this as the SDA and SCL lines are 5v tolerant. Dose the 5v pin and the NavX Micro still NEED 5v?

Then even this page suggest using the USB preferably.