When MF sold some of their stuff over to SPAR, I didn't agree to the change, because at the time I was unable to locate any further information. Regardless of that, I received a badge in the mail a few weeks later, as well as some paperwork for a $7.00 assignment that they expected to take "no more than 2 hours." I called to inform them that I was not interested in that, and that I never signed up for that. My explanation was that "You don't pick your assignments. We assign them to you." Great, but that's not helpful to me, when it doesn't fit in with my existing schedule. You can't just decide when I have to leave my house 2-3 days later to complete an assignment for a company I didn't agree to, when I might have other responsibilities previously. Furthermore, when I tried to cancel this assignment, I was treated as though I was ungrateful for the opportunity. I'm not really sure I follow that logic, since I explained the whole situation. They wanted me to mail back the materials on my own dime, and asked that I no longer use my badge (I'd never used it!)
I've never actually worked for them at all, but that's my experience.