We are just doing 802.1x authentication. No VSA for QoS/rate-limiting. Mimosa doesn't support it yet (but I think it's on the road map)
We use the bandwidth rate limiting in the A5. We offer only 1 tier of service right now so it's a very straightforward/basic setup.
Also worth noting that we provide every customer with a G2 unit (in router mode) so we have a known L3 device on the other end of the C5.