They are just too new for me. I know I mix steam,turbine and diesel, and for that matter R.Roads, but I have to draw the line somewhere!
Whatever you put on your layout Bob it look good no matter what era you run. Besides the only thing you have to change is the trucks/cars on your layout to make them look newer era. I do on my farm I have some trucks from the 60/70's and then I have some new trucks and cars.