Sunset did their T1's around 12 years ago. Three prototype versions were offered in 2 and 3 rail. The total production run was 220 models. I DCC my 2 rail "modernized" production version and it will handle a 9 car heavyweight passenger train (mostly PSC Pullmans) up the 2.2% Horseshoe Curve grade unassisted. Add a car and it needs a helper. Like most Sunset 3rd Rail steam locomotives Scott Mann struck a nice balance between detail, performance, and price. Three months ago a mint 3 rail Sunset 3rd Rail model of pre-production T1 6110 was listed on eBay and I was fortunate to buy it for $599. At some point I may have it 2 railed but for now it looks great over my desk. A factor favoring Sunset over Williams and Weaver T1's is that their model of the 50 production T1's correctly carry train phone gear on the tender. If you're in 2 rail I highly recommend any of the 3 Sunset T1 versions.
Ed Rappe