First, a bit of Forum etiquette: If you are asking a new question, please create just one new thread. You posted to five other very old threads that only happened to refer to Kinetix 6000 and feedback topics, and resurrecting those threads to ask a different question is not helpful to the Forum.
Kinetix 6000 multi-axis servo controllers are a fairly mature motion control product, and they support several types of feedback, including Stegmann Hiperface. Hiperface encoders are supported both for motor feedback and for auxiliary encoder inputs.
Both the single-turn SRS and multi-turn SRM type encoders are supported by Kinetix 6000 motion controllers.
I do know that the XKS wire-draw string encoder, even though it's a Hiperface product, does not work with Kinetix 6000.
There are dozens of different encoder part numbers made by SICK that support Hiperface SRS or SRM. Any of them will work with Kinetix 6000, so there is no single 'best' encoder part number.
There are three families of Kinetix 6000 controllers; 6000, 6200, and 6500. Any of them will work with Hiperface SRS or SRM encoders.