It varies a lot.
What I really like is the ability to research using online libraries and other sources. I sometimes feel that teaching good search techniques is a skill that is sometimes overlooked. It is one of those generic skills that underpins online learning in my view. Obviously this is always going to be dependent on the range of sources available and, of course, on how reliable those sources are. And yes, researching topics for end of course dissertations has been very much my high point in online study.
Where I have problems – online tutorials can be useful (when the technology doesn’t let you down) but I still find I can get far more across and engage more in a face to face tutorial. The other downside is when the module refers you to a paper which is online – older modules still have course books and readers with the relevant secondary / primary source material. Online It is variable access. Not helped by my personal preference for long, text dense material (as is common for BA / MA study) which is also not always easy to guarantee.