Fox warranty via Silverfish is excellent and fast in my experience.
Warrantied a set of 36’s twice recently (an un-identified knock), they are 18 months old.
1st time I sent them back, turnaround was literally 1 day (e.g. courier delivered them in the morning, they fixed and sent them back out the same afternoon!) so 3 day turnaround to me inc shipping. new damper fitted.
Unfortunately that didnt seem to do the trick, so they went in again. Again it was certainly <5 working days turnaround from sending them off to having them back in my hand. This time new bushings and whole new CSU – or rather they had fitted a whole new top unit including fresh stanchions and uncut steerer tube.
Obviously not great having to warranty something, but their turnaround and service has been excellent and I now basically have a set of forks where only the lowers and air shaft are the originals.