I recently purchased the G0752Z.
Upon utilizing the tail-stock to drill a hole I unintentionally exceeded the 61.5-mm travel, the drill bit caught and the hand-wheel spun in my hand nearly catching my thumb.
The internal threads were buggered and will be replaced. Prior to using the tail-stock I found the quill very hard to advance or retract. Upon disassembly and very close examination of the guide slot I find very small pimples along the edge of the guide slot. These micro-pimples were formed from the quill slight rotation against the metric guide-screw M6-1x12 atop the tail-stock. I carefully and cautiously using a very fine file, filed the micro-pimples off and the tail-stock quill worked easy and smooth as it should. Confirmation from Grizzly, the tail-stock quill is NOT hardened, to resist such anomalies.
I will in the future order a second quill, rework the guide-slot for slight chamfer for these micro-pimples to accumulate in and increase the depth of the guide slot to create a natural stop to reduce or eliminate running beyond the quill travel.
The guide-groove needs to be closed at both ends to create a natural safety stop. When your attention is on the rotating business end, the tail-stock is less a concern and needs a safety stop for the operator and machine sake.