So most of my bikes had threaded adjusters whcih I had no probs with
I just took the rear wheel of my XT and serviced the brake and cleaned up the chain. After re-fitting I went to set the adjustment 30-40mm stated in the manual.
On one setting the free play is 50mm
On the next setting it is 25mm
So they are convient and allow you to quickly align the wheel but not as fine tuneable as threaded adjusters.....
So I risk having the chain too tight at 25mm.
Or too loose with the possibility of the chain rattling around or coming off..