I'm surprised to see all this- I've never had the issue. I'll keep ,my eye out though.
I do like Informa, and actually got paid yesterday for a bonused shop- and it was a 2- part shop. The second part hasn't even been completed yet, and they still paid- early. maybe it's the feedback that's helped.
One time they did try to deny payment, but I really fought for it, and they were agreeable in the end.