I just joined Webflow a couple of weeks ago, and so far, I love it. It's the only CMS (besides, perhaps, Webpop, which is more expensive) that I have found that allows full design control.
I do have one general suggestion: The video tutorials seem to be more promotional than instructional. For example, I was searching for a way to create a class that specified only a box shadow, which I could then apply as a sub-class to multiple elements. When I searched for information related to working with classes, all I was able to find was the video "Using classes and adding styles." This video talks about how great classes are, but it doesn't provide detailed instructions for working with classes.
I'd like to suggest that you continue with the promotional videos you have been creating, but also start to provide tutorials that are more geared toward detailed instruction.