After poking at the HP/Aruba AP555 I have transitioned to a pair of Engenius EWS377AP access points.
Initial setup was using the ezMaster controller. This worked really well but presented a few cons I was unwilling to live with. Mainly independent monitoring of the APs via SNMP is not possible and the need to have the controller going to make changes. They are now operating in stand alone mode. Another issue was lack of monitoring in the controller tied tot he APs.
I am hopeful openwrt support will come to these units at some point. The factory firmware works well, just seems a bit limited/restricted in options.