Performance of rich edit control vs. regular edit control

The rich edit control will drive me to the poorhouse :-)

I have a test program that bombards another program with commands.  The details are not really important.  The test program has an output window, created with a rich edit control, so that it can easily show stimuli, responses, error conditions, etc. in different colors and to avoid the text-length limitation of a lower-middle-class edit control.

When the test program talks to the other program, it achieves somewhat above 60 commands/second and uses 2% of my desktop's CPU time.

When it narrates its activity (commands, queries, query responses) to the rich edit window, it achieves 20 commands/second and uses 70% of the CPU time.

Three-part question

Are you surprised?  I was.

Do you know of any rich-edit-control tricks that I should be using?

Can you think of any existing output-only scrolling text windows capable of multiple colors, or write my own for this application?

Thanks in advanced for any help

Dave