Funny you should ask. I am driving the Legacy Aeris with the 7BSST/2. The 7B's are coasting seeing how each woofer has a 500 watt amp. The Aeris has 95db ratting 1 watt 4 ohms.
The other Bryston on the floor is a Bryston BIT-20.
I had Infinity Epsilon before driven by 2, 4BST. Then I upgraded one of the 4B's to a 4BSST/2 for the highs. I blew both of the EMIT's several times over the course of 10 years. I had spare's but they went again. As you know it's hard to get parts for the Infinity's. I sold the Infinity speakers as is 3 1/2 years ago. I then purchased the Legacy Focus SE. In my opinion the Legacy have similar sound to the Infinity Epsilon's.The Legacy's had more control over the bass than the Infinity's. Also I thought the Legacy highs were smoother along with more information.
The Aeris is a different beast than the Focus SE. You can tell they are from the same family but the Aeris just takes it up several notches. I have not heard the new tweeter in the current Focus SE so I cannot compare Focus's.