Updated to the new version of Synapse to try Element X, but went back to the regular app due to the lack of features, particularly the image resolution prompt when sending media.
That's ended up becoming a global setting, which merged a few days ago (https://github.com/element-hq/element-x-ios/pull/3467) so hasn't been released yet. We're catching up on features as rapidly as possible - meanwhile i'm surprised that the advantages of the new app donn't completely blow away the old one.