Even for fast roaming hops on WPA2 Personal (which is my real issue on the latest Airport Extremes when trying to use VoIP), do you think placement is an issue? As I can't adjust the power of the Airport Extremes and I can't disable the 2.4 Ghz radios, I would think that as long as my placement is half-decent, the 5 Ghz hops would be quick enough, as long as the APs and the client support 802.11r and k, which per your's and other's comments, Apple's APs and 10.9 or later does.
Btw, I've been monitoring my OS X RSSI levels when roaming on AC, and the MacBooks seem to always be less than -70 dBm (usually reaching -78 or -80) when I'm near the next AP. So I'm thinking my placement isn't the issue. But I will fire up the tools you recommend next.
Btw, I've been monitoring my OS X RSSI levels when roaming on AC, and the MacBooks seem to always be less than -70 dBm (usually reaching -78 or -80) when I'm near the next AP. So I'm thinking my placement isn't the issue. But I will fire up the tools you recommend next.