I had a very strange experience using winscp beta 5.
I moved a lot of files from one location to another using winscp.
However I had a very strange experience in that I afterwards checked the synch using FreeFileSync and it found a lot of conflicts in filesize - often of some bytes.
My contacts are at https://pastebin.com/a7GKtLCF
if you need to contact for further details.