I've started using Synchi (3.3) for editing templates and functions, and it definitely makes that job nicer.
But I've found a bug in the page/post editor, Synchi takes over and make 'HTML' editing default, and then when i try to switch to the 'Visual' tab the editor container-frame is not fully expanded (only about 10px height is shown) and if I navigate back to 'HTML' the frame stays small and uneditable.
I guess it must be a conflict with MCE?
A feature request would be to add a setting which allows a user to choose which areas of the WordPress Dashboard the Synchi plugin is active on.
I can repeat this bug in firefox and chrome (on linux).