I have two of the big boys and one challenger.
The one of the big boys would be the original tooling from Con-Cor this one I can't speak on as I bought it as non operational and haven't repaired it, it's motor is destroyed. I'm told the original tooling wasn't all that great, that thye had motor problems. I have toyed with the idea of remotoring this one.
The other big boy would be the second tooling I bought this one new in the late 80's and it has seen many hours of running haulling fair lenght trains, I was normaly limited to the third track on an N-track set up which had tighter radius. It is presently broke down as a wire left go this is a miner repair that I haven't bothered with as I intend to DCC it when I repair it. I mainly model Canadain National, so I should get a string of UP cars and a UP caboose for with this engine when I'm running it at train shows. I praise the newer big boy and the chalenger as they are good running, croud pleaseing motive power.
I do believe if you are going to run yur trains in public that it is better to have steam engines running as they are groud pleasers, with the rod action, unlike desiels no mater how well detailed. It has always ben a joy to watch people, particularily children as they watch the big boy.
Brady