I use both daily. I came from pretty much a pure Adobe background, and have been using Adobe products for about 25 years now. The shop I took over a year ago did everything in CorelDraw and Flexi. I've gone as far as uninstalling Corel on my computer, (sorry Corel lovers, I can't stand using it) but my ancient Graphtec plotter won't run without Flexi. I've learned to like a lot of the features that Flexi provides, and don't think I could get along without it now. Illustrator is a much more robust design program, but it is really intended for print use, not vinyl cutting. It can do it, but Flexi has some features that simplify a lot of the work I do in Illustrator. Converting raster images to vector, for instance, works fantastic in Illustrator, but it creates a ton of artifacts that I end up having to clean out of an image if I want to cut it. Flexi doesn't always do as good of a job, but it usually creates a cleaner file that can be cut with minimal editing. We're due for some equipment upgrades within the year, and my plans are to maintain a Flexi Design license in order to have access to all the old files and still use some of its design features while running everything through Adobe for output. As for converting Flexi files to Illustrator, the only way I know of is manually opening and exporting them all one by one. I'd love to find a way to do it in batches, but so far, I haven't had any luck with that.