Undecided. There is a technical issue here:
In the "old" editor it works like a charm, hmm...
What exactly are you interested
I
always just want to see the quoted message while replying above. (This is what many users do).
In new editor it is not comfortable, but complicated.
After pushing the reply-button there are these steps to do everytime:
New editor:
1. Tap on [...]-button to expand the quoted message
2. Since the cursor mark jumps from first line into second line, I have to manually put it back into first line
3. Now I can start to write.
Old editor:
1. Just write
- like in other mail clients (because quoted message is visible and cursor mark is in first place)
This is why I (and some others I know) need the old editor.