Can’t reproduce the echo problem.
Note that when you break apart the clips the audio is still connected to the video so you shouldn’t lose sync unless you physically move one or the other clip out of sync yourself. Make sure you have “show connections” checked in the clip appearance window on the lower left of the timeline.
Keep working with it and I think you’ll find more and more to like about it. That’s my experience anyway coming from an FCP user since 1.25.
What I found to be very helpful was the Ripple Training program. Larry Jordan also has some good stuff as well as others. Nothing like free so take a look at this too: https://www.izzyvideo.com
Good luck!
NT