I'm a current A3 owner and have heard a couple of Vivid’s. I would recommend the A3’s. IMO they are a better allrounder. Both are exceptional so really, I’d recommend listening to both if you can. The Beryllium tweeters Magico uses are smoother without losing detail. Unlike Focal’s implementation. I would say they both have excellent imaging and layering. Bass is solid in the A3’s fast detailed and quite deep for the size. Can’t really recall all the sound profile of the Vivid’s been too long. I preferred the A3’s sound but they are just a black box so the Vivid’s maybe a nicer looking speaker to some. Both are heavy, Magico’s being 110lb each. The Magico cab is a work of engineering excellence with zero cabinet resonance. I noticed this after being a Open Baffel owner for several years. I like the Vivid’s but I think the Magico’s are for me have the better sound, more engaging, dynamic, non-fatiguing and supper detailed.
I cannot listen to Focal’s due to how bright they are, coming from B&W’s which I also find a little on the brighter side (not as bad as Focal’s) you may prefer the Vivid’s.
I’ve used Coda, Sim Moon on my Magico’s both sounding great, I’ve also used a 30wpc vintage amp on them with surprising results so they can be driven by less power than I would have expected. Pass labs gear sounds excellent of the magico line from my reading a good match.
I have a 14x 22 room and the A3’s work excellently in it so I’m sure they will be fine for your room as well. I use my Magico’s for both music, TV, movies etc. in a mixed living room environment they work well for all. I’m going to try a tube amp on them next lol.
One thing you will find is both will show your up-stream components shortcomings like a lens, the A3’s have put me on a total upgrade path due to their abilities to retrieve detail and dynamics. I’m not sure the Bryston will be at the level of either speaker to be honest. Granted I’ve not heard a new Bryston in years.
Good luck exciting time for you a head, either way you go as both are stellar.
