DAR_KO just wrote a nice comparison between KEF's LS50 and ELAC's Uni-Fi BS U5 Slim
http://www.digitalaudioreview.net/2017/04/elacs-uni-fi-bs-u5-slim-is-a-righteous-contender/
Andrew can build a mean set of speakers. I do believe he was part of the design team at KEF when the LS50 were being designed.
I dumped my Debut B6s for a pair of LS50's, but I'm going to give due consideration the Andrew's newest Adante line. When it becomes available.
Onward and upward, as they say.