Encoders and index homing

I'm looking at purchasing some Us Digital encoders and had settled on
the E5D's. One of the options I'd like to make use of is index
homing. The one down side is I've got a slave driven x axis.
UsDigital has the option of having an adjustable mounting ring
[Option "R"] which allows a person to rotate the encoder by up to
15degrees for this very reason.

However, while this seem's to cover all the bases. I noticed on the
UsDigitals website that it says it recommends the use of a centering
tool when using option "R". This would lead me to believe that while
in theory this R option should enable me to zero out my two index
positions so they work w/ the slaved homing, this very well may not
be the case. If in the act of adjusting the mounting position of the
encoder, it gets off center then having this option is kinda moot. My
other option would be to simply loosen the hex set screw in the wheel
and rotate it until the index is seen by the control??

I'm looking for opinions of those who have installed these encoders
and can offer any advice as to if this is really a problem or not.

Might as well find out before I leap..

Thanks guys

Jarrett Johnson