Hi Jesse, Sorry I have been unresponsive - I've been too busy with work etc. which is unfortunate because I think what you have done here is fantastic. I wish I had more time now to discuss this new feature indepth but, alas, I have to race off to work again :/
Regarding the border redrawing, this is most likely due to the border not being included in the CSS values for width on elements like li and ul. I know it's tricky to include pixel units into an em value, but I find just adding .1em or .01em or something in between to those widths generally solves the problem. Again, I wish I could go on. I'll try and find time on the weekend to reply more fully. I'm thinking we could make this code into a module that can be added onto Superfish as an option. A plugin for a plugin. Cheers Joel Birch.