Pros
The only pro is that you can work from home.
Cons
Cactus/Editage does not offer salaried positions or references to freelancers. Your name isn't given to authors so you cannot build a "reputation" for your editing services. Doing this job will not advance your career or earning ability in any way. Extremely low pay (less than US minimum hourly wage) for meticulous editing and what amounts to a semi-translation/semi-peer review. Constant demands that you do work for free. If you get these, you can email them and tell them you won't do the job but it's very annoying getting these requests. Lately, almost all assignments have less than a 48-hour deadline. Given the amount of work the documents need, this isn't reasonable. These jobs can't be accepted if you want to keep a good QFR and your deadline conformance at 100% (and they don't pay you for jobs that go over deadline). Even though there are a lot of jobs on the Whiteboard right now, no freelancer can take them because the time given is too short.