I used Nikwax for several years but switched to ReviveX on my breathable waders as that was what Simms recommended. Waders being underwater for hours at a time is one heck of a test of DWR, along with sitting and kneeling on rocks/gravel, etc.
Overall I think the ReviveX works better and lasts longer on my other gear that I've used it on but its a little harder to find.
X2 on the ReviveX
