Sweet. Thanks for the feedback. Interesting capabilities and price point in Cisco's SMB line. I like that you can cluster up to 16 without a controller install. Definitely some enterprise features on board, but with simpler and more direct management, which is nice.
So I learned something that sucks yesterday and it has resulted in me RMA'ing my unit and sticking with UniFi (ugh).
Cisco pre-sales said that I could add mixed models to the same Cluster, however, I found in the manual (and confirmed with Cisco) that this isn't the case. All AP's in a cluster must be of the same model which sucks!! I don't want to spend $300 on another WAP581 for my shop that will have at most 4 clients on it ever when the UAP-AC-IW works just fine for that location and it cost me $60 :-(
I also learned that the Link Aggregation is Static only on the WAP581 and it doesn't support LACP which is also a bummer but it would still work with my switches.
This leads me to believe that the Grandstream GWN7610 would be a better option for me since it can (I verified and have seen it work) act as the controller for the GWN7600. The downside is that it isn't a Wave 2 AP but at least it works.
For now though I will just stick with UniFi as I'm tired of spending money on AP's.