I started out in O gauge with Lionel 027, but even as a kid I didn't like the way 3-rail track looked- not even close to the real thing. After almost 30 years in the hobby the semi-scale engines and cars were replaced with 3-rail scale models, but I still couldn't find the perfect 3-rail track. It was only after I saw what some individuals were doing with code 148 Atlas 2-rail on the OGR Forum did I find my ideal track- stud rail.
Like the name implies, it's a rail with studs sticking up between the ties of the 2-rail track. The stud rail is a 1/2" tall piece of sheetmetal with rectangular sections knocked out at the top, leaving studs protruding- this rail is supported by Midwest cork roadbed on either side of it. A brass slider is clipped on to the rollers and contacts the studs. This track system acts like 3-rail in most aspects, but when the track is ballasted the studrail is barely noticeable. It also uses code 148 Atlas 2-rail, better-looking than any 3-rail track system IMO.
I contacted the individuals who pioneered this track system, and one of them even sold me his remaining supply of stud rail ( they both have since gone pure 2-rail). I then proceed to lay down a test loop with a siding, which worked better than I expected. I was planning a large 2-level layout with over 500' of track, but getting the studrail made proved problematic- most shops in LA wanted too much money to fabricate it. I'm now in the process of designing my own tooling so I can make as much as I need, and even offer it to anyone interested after I build a test layout.
Like anyone interested in scale, I'm getting into the MTH scale-wheeled diesels as well. The scale-wheeled diesels and steamers have a '-2' suffix after the part number, and that gets you an engine with scale wheels, fixed pilots (diesels), and mounts for Kadees (you supply the couplers). These units are a big hit with the 3-rail scale and 2-rail crowds, since they can be run on either 3 or 2-rail track with a flip of a switch and a change of wheelsets. The scale wheels can even be run on square profile track like Gargraves and Atlas 3-rail, but will dip a little in the frogs of some 3-rail switches.