Good speaker match for the Devialet, Magico ?

I think you might want to look at Focal or KEF, which I have both heard on the original 300 watt offering. I love the KEF 50s especially, or any of the mid-range studio speakers by Focal.

Because Devialet is French, they are frequently paired with Focal in France.

BTW: very impressed with this unit. Can easily recommend it as one of the best components out there, especially with digital content.The control unit almost seems like it has jewel like movement.

I have not heard the Devialet, but I own the Magico Mini 2 in a room slightly smaller than yours. You can check out my system page. If you are considering Magico speakers, you should listen to the S1 which is a floor standing two way which is supposed to be even better than the Mini 2. Your room is large enough to consider larger Magico speakers because with their sealed cabinets, they can be used in slightly smaller rooms, IMO. You will need lots of power with Magico speakers though. They are not easy loads to drive properly.

If I where you I first would take all your time to listen to some speakers in the price range you are looking for. because it Always is a personal matter. After this I would look for an amp what fitts best to the speaker you bought. Have fun and take your time.