Sonos Era placement, Era 300 or 100?

[Paulflexxer]

My room isnt perfect, but still want to try getting surround sound in my living room. Currently i have an arc, and soon getting an Sub from a friend.

Now to the rears, where the problem begins, how should i place them?

Blue marks would be my idea, with wall mounts.

And i think the era 300 will be to big for my room.. and hard to place, so should i got with the 100?

My Main use will be mostly tv and atmos movies/regular movies.

 

[staticV3]

The Era300 with its four tweeters pointing in all possible directions I cannot imagine would perform well as a dedicated rear surround speaker.

The Era100 seems like a smarter choice here.