Pros
The people are reachable and reasonably nice, and they will sometimes advocate for you, which is good. The expectations frankly aren't particularly high for a staffing agency, and they meet some (but not all) of the very low bars.
Cons
They frequently made mistakes in pay (not just for me, but for many others) and wouldn't realize it themselves. Like very often. Check your pay stubs against your hours!
If you ask them a question over email or phone they'll say they'll get back to you and never do, so you have to keep following up over & over. Any email question would require several layers of explanation and usually I'd just need to get on the phone and explain the simple question.
I would track my own vacation because they kept messing that up too. I don't even understand how that's possible, but somehow they managed to do it.
All in all, not awful by any means, just incompetent in surprising and potentially harmful ways.