Both are thx ultra rated. My room is larger than yours and I’ve had no issues with the 1723 S, and at no point has it felt like they are not up to the job.
Due to cost and flexibility I also use 1961 speakers for height and surrounds and they have really surprised me! Arendal have done a great job there where even their smallest speakers sound large and full!
If a cost is a concern that’s exactly why the S series exist, you are getting the best performance for that cost.