We are using DevEx vcl-Components as visual components.
I have a small sample project, that shows what is happening right now.
I'll provide this in a several message.
Just to describe it here:
DevEx is reading and writing rtf to TBlobField by using TStringstream with default encoding, what should be fine because rtf is 7-Bit ASCII.
We are using TBlob in Aurelius to save datas.
But as you describe in docs we should access TBlob using AsUnicodeString.
Here is a screenshot, to show what is happening