Pros
I've been with this company going on five years. As far as part-time gigs go, particularly if you are just starting out in transcriptions and captions work, you truly don't get much better than this. They offer a tiny compensation for on-the-job training and practice, and then from there, you essentially design your schedule and how much or how little you'd like to work. Keep in mind, most of the work gets posted according to PST (which can result in later/odd hours for those of us on the east coast). People get bent out of shape because there isn't much room for benefits, but keep in mind, this is contract work, meaning you're going to have to find other ways to receive benefits.
Cons
It's not always easy to find consistent work, but this isn't something the company can always control.