The C420 sold by Rivarossi was the old MRC/Lima one, and did run well.
As for the 2-8-8-4, I don't think they made one. Their articulated stable consisted of 2-8-8-2, 4-8-8-2, 4-6-6-4. and 2-6-6-6. They ran from fair to good to really good, depending on what incarnation and locomotive. The really old ones had a 3 pole open-frame, square motor (fair), 3 pole round motor (good), 3 pole inside-the-boiler-with-flywheels (between good and really good), and pretty much state of the art for when it was made (DCC ready) a'la the 2-6-6-6. They've since gone out of business, but that doesn't mean the stuff is junk.