Mike, much as I'd like to see an H20-44 (being a UP fan), I don't think the 70 tonner comparison holds up as a business model. Even though both engines were produced during about the same time period, there were about 300 70 tonners built compared 96 H20-44's. The 70 tonner went through three phases but the body type was essentially similar for all 70 tonners, making it an easier model to produce. 70 tonners were used by over 25 Class 1 railroads and numerous shortlines and industries. I don't know the total number but there are a sizeable number of 70 tonners still at work today. The last H20-44 was retired about 1970 and only because the AC&Y and the N&W managed to keep FM locomotives running longer than other railroads. The 70 tonner is almost iconic as a small switcher and every railfan has seen one. The H20-44 was an oddity that hasn't been seen on the rails in almost 40 years and has none of the endearing qualities of things like UP turbines or Baldwin Centipedes. It was neither a switcher nor road engine but was sold as a transfer engine, a job that was taken over by Geeps early on. Other FM locomotives. like the Trainmaster, have a big following among railfans. The H20-44 just sort of slipped into oblivion.
Again, I'm trying to think like Atlas or Walthers. Is it worth it to produce and H20-44? Will we make money? Even the H10-44 made more sense for Walthers, since it was sold to 22 railroads and their "hometown" railroad, the MILW, was the second largest user. Do we retool it and make an engine that only sold to five railroads? I's like to see it done but I don't think I could make a business plan for it that made sense.