A place for getting quick jobs, assuming there are any available
From the perspective of an on-demand worker (as opposed to a regular worker, who does administrative work for the company), this was an okay place to work at. You call, tell them you would like some work, and if you're lucky you can go to an available placement the very next day. (If you're unlucky, you'll have to wait for a while with no indication when jobs will be available.)
My pay was minimum wage; I didn't bother to ask if there were any way for my wage to be raised, though I do know that if the place that requested temp workers wanted to hire you personally the wage will go up by $3/hour, the commission rate of Liberty Staffing.
In my experience though you can choose in what capacity you'd like to work at (e.g. full-time/part-time), they don't actually get much requests that ask for anything less than full-time. That said, your scheduling is pretty flexible; I've overheard other people ask for and get a(n unpaid) day off so they can go to job interviews, for example.