Today I did my first advanced spreadsheet on LibreOffice after switching to Linux, and it handled itself pretty well. I had to search for some features on the web at first, but after I got it down, I felt comfortable using it. Also, LibreOffice’s default menu layout is not pretty, but I can find all of the functions with just a click, unlike MS Office’s ribbon menu where I had to click around to find what I was looking for. Sorry for bad English.
I usually work with MS formats on LO (only because they need smaller space for small files, in larger files, MS formats are objectively bulkier). My observation is that MS messes with formatting of files made on LO, no matter which format you pick… even with whitespace of otherwise plain unfomatted text at times.
It is definitely a MS issue, and it is not about formats they have made public.