If you are dead set on autnomous, WLSE is probably your best bet.
I worked with some third party managment software before for cisco access points and it wasnt very fun.
You can ebay used controllers pretty cheap these days. Once the 5500s are released you may even see them dip a bit lower ...
"Satisfaction does not come from knowing the solution, it comes from knowing why." - Rosalind Franklin
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