Not sure where you read that Yamaha has a reliability issue. I'm almost certain Onkyo has had more issues in the last 5 years with their AVRs. In fact, I would say Yamaha has a higher reliability rating than any on your list as far as MFGs go, but Denon sometimes have returns for not giving better manuals.
That being said, Onkyo is a good unit, so are the other two. I would choose the Onkyo out of this list, but I would definitely try to get a higher model refurb from A4L though.