The most amazing thing about this program is that there are so many different courses to choose from! It's really helpful when I am working as part of an agency or freelancer where my clients want me to learn new techs but don't have time themselves.
They send through work which they trust me enough to know what tools will help them best. Also it has given us more confidence having seen other people use certain software products before trying ourselves (iPad Apps vs Google Sheets). There isn't much i dislike at all - maybe just how busy life gets sometimes! Make sure you do some research beforehand if you're unsure whether something would be useful to others too; e.g., our first course was called "Create Your Own Website" but we realised quickly after putting up our site that not everyone had heard/understood exactly what we were doing.