I am taking an online course right now, it is my first. It is OK I suppose, but I would rather take it in person. I waste a lot of time writing and editing my writing. It takes more energy to communicate by typing than by talking.
This particular course though is very well put together and easy to navigate, so it is a pretty good experience so far.
The drop out / fail rate for online courses can be pretty high in general. They aren't the best for a lot of folks, particularly those without very good reading comprehension and decent writing skills. But some people really like the convenience of working online v. keeping to a schedule in person.