I have mostly 3 rail a lot on my layouts but also some 2 rail scale track. Have used Atlas, Gargraves and old Truescale road bed with hand spiked rails. My switching layout I used what I could find of some used Roco track and switches, and Gargraves in the yard this works well with DC. If you are buying the MTH engines with the Proto 2/3 you can buy them with scale 2 rail wheels or with 3 rail wheels; then you can simply take off the center rail pickup flip the switch from 3 to 2 rail and run them on the Gargraves 2 rail turnouts with the high rail wheels. You can also if you get an engine with 3 rail Hi rail wheels buy a replacement wheel set for the diesel engines for 2 rail wheels. The MTH proto 3 engines will run on DC DCC or best with the MTH control system.
A friend with a large 2 rail layout has been very happy converting several engines to battery powered with a remote control.
Here are some photos of me running 2 rail on a dual gauge club garden railway. The CN engine is Weaver 2 rail brass with Lionel TMCC control system. The CP Steam is 2 rail MTH, the SP diesel 3 rail proto 2/3 with the center pickup rollers removed 1 screw and switch set from 3 to 2 rail and both running with MTH DCS system. The TMCC and MTH DCS I can run from a distance for speed and sounds with hand held remotes.
