They were one of my very first MSCs, 5 years ago. I set up my account with a special MSing email addy and signed up for a shop. Totally forgot about the shop and forgot to log in to that email addy. They called me a few days after I was supposed to do the shop and rescheduled it for me; afterwards they paid me on time, and didn't penalize me for the mistake.
I have done 3 this year and 10 all together. They have always paid me and usually pay within 1 1/2 months from the completion of the shop. I also have found them easy to deal with. That being said: I do not feel that they pay enough to compensate for the amount of work that the report requires. That is why I haven't done more for them.
bigcardsfan2 ~ AboutFace is a reputable MSP. Straightforward requirements, feedback following reports, and payment according to stated terms. AF is in the list of MSPs at the bottom of the page; click on it for more information.