So, I copied over my level 20 dark path monk Saalutaball and respecced her for the ninja spy PRE. I really like the water strider and shadow fade although the timers are rather low on them. 30 seconds on water strider and 1 minute on shadow fade.

Ninja Spy I- given at 6th level. shadow fade of 1 min is good for this level, but it would be a little better implemented if it had same timer as haste spell. i.e. goes up 6 sec per level after original implementation. (2 min 24 sec at 20th if implemented correctly)

Ninja Spy II-given at 12th level. water strider for 30 sec seems a little low, should be at least 1 min for a 12th level ability and again should follow the haste timer and gain 6 sec per monk level after 12. Even staying at the 30 sec start and going up 6 sec per level would be 1 min 8 sec at level 20, hardly game breaking. 1 min 48 sec if it started at 1 min as per my earlier suggestion. (Although I realize there aren't many places where you would need to run over water or any other liquid for almost 2 minutes)

Unless you are planning to add Ninja Spy III at 18th which would double the timers on both or add time to both...could also possibly double shadow fade timer for ninja spy II and double again at ninja spy III...and double water strider at ninja spy III as well, these would be good implemantations as well

Just my thoughts, though...take them as you will

Saal