With IPSOS, I look at each job type on a case-by-case basis. Most of their shops are fairly simple, but some are simple and fast, and some are simple and lengthy. Sometimes their instructions and surveys don't match. I won't do their cell-phone or other technology shops at base price, but there's another of their regular shops that I'll take at base. Some of their fees seemed to have actually gone down lately, so I won't do those. They had a high-end shop a couple of years back that paid well, but I haven't seen that one come around again.
On the plus side, they pay on time, every time, and I've never had to chase them for fees or bonuses. The editors are pretty easy to deal with, and the few times they've had questions, everything was handled quickly and easily.
I learn something new every day, but not everyday!
I've learned to never trust spell-check or my phone's auto-fill feature.