To move between design and code view in tinyMCE requires opening a popup window with an unformated presentation of the code. It is difficult to view because the text is not wrapped.
Using JoomlaFCK the code is wrapped, which makes viewing code more appealing.
To add or manage images in tinyMCE, there's no upload or browse option, so you have to know the name of the images and where they are located. Additionally, if you want to add new images from your HD you would have to go to your FTP program to upload them.
Using JoomlaFCK, the image manager includes upload and browse options, so you upload new images or browse the image directory to select images to display.
Awesome to find an open-source Editor that offers so many features!