...They also used a Lionel drive with a GE motor, do you have any information about those drives and motors? I have read they are not much better then the Kader-Bachman units, but I don't have any first hand knowledge of either...
The original Lionel engines were released with a very heavy chassis with a GE electric shaver motor in them. They did not come with flywheels, nor were they needed, IMHO. The detail was good for that time, and the trucks details were well represented. The castings for the side frames were on the lines of the BB locos available at the time. It was quiet, even with the shaver motor, and the chassis, coupled with the 8 wheel drive, made these locos good pullers.
The engine I had, was not part of a set and were released as separately available items. They were good engines, and I was looking forward to the release of the GP-30 with the same chassis. It never appeared IIRC with the GE motor, and heavy chassis. Just a typical Bachmann chassis of the time.
I was in the process of painting it for my favorite road, when they released a set with a properly lettered loco in it. I sold my single unit and bought a set with the money. To my dismay, I found that the engine was a Bachmann, as well as the cars. Bachmann's quality wasn't what you would consider good in those days. I was disappointed. I have kept the set intact though, and even have run it around the Christmas Tree for several years. Now it resides on a shelf in the original box. Surprisingly, that pancake motor still runs, although I doubt that I will ever run it on rails again.
Personally, if I ever come across another GP-7/9 with the heavy chassis, 8 wheel drive, and motor again, I will pick it up, if possible. It was IMHO, a good locomotive for the time.