If you use cDot mode on your Netapp you should get most information’s you need.
The current special agent lags some info like home port/home node information for interfaces but that’s not the big problem. Also the snapshot information are not complete.
I have around 50 Netapp systems in our different monitoring systems and have no problems with the special agent. Only beware if you have systems with many many quotas, then you should manually comment the quota sections is it take a great amount of time to retrieve this information (tested on a system with over 4k quotas 
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