Brian, I have run my MTH with standard DC power supply both the USA trains and the bridge work supply's. not sure about the 8' dia but it does my 10' no problem. if you buy one of the upcoming ones they will have DCS 3.0 it is a nice system that works on just about everything DC, DCS, and DCC. they are a lot of fun with DCC with all the controls of sounds and lilghts but sometime its just nice to toss it on the track with DC and play. As soon as I get my Gray Challenger down I'll post some pictures and maybe a video.