Went in with CAD experience so I can't speak for how well Gao teaches it, but overall I'd say that he's a fair professor. Homework and a lab every week, plus a final project, but no exams. Most of the class is learning drawing conventions, working in SolidWorks, making models, and turning the models into drawings. Depending on your TA, prepare to have your homework put under a microscope though.
One word of warning, the final project is relatively simple but is accompanied by a tedious report. If you can, pick people who you know won't slack off... Don't ask me how I know.