There seems to be such a wailing and gnashing of teeth over the conflicts between prototypical scale and American Flyer offerings, particularly on the Yahoo board for S scale (inaccurately described as "S gauge") modelers. American Models and SHS had the solution with different approaches: people ordered products with "scale" or "high-rail" wheels directly from AM because they found it too difficult to get into hobby shops. The appropriate couplers came with the wheels, but those who wanted high-rail wheels could easily swap the massive couplers with Kadee couplers themselves. SHS provided both sets of wheels with their offerings, and users could easily attach Kadee couplers on their own. Des Plaines Hobbies' S Scale America takes the SHS approach for most of their products.
As Rusty notes, it's a simple matter to swap wheelsets in the Lionel American Flyer diesels. Those diesels have enough detail to satisfy many, but not all, modelers who demand prototypical accuracy. Steam locomotives are another case for everyone--AM, SHS, Lionel, and perhaps MTH--because of the complexity of the wheel arrangements. AM and SHS required customers to select one or the other, prototypical scale or high-rail. Lionel only offered high-rail. (Fred Rouse for a time did conversions for the Y3, but those conversions were expensive.)
Rolling stock should also be as simple. It is for AM. It was for SHS. MTH insists on two different part numbers instead of adding prototypical scale wheelsets for a single part number, making problems for inventory management; but its easy to swap out wheelsets in the trucks if the desired version is not available. This is where Lionel can make improvements. Yes, the cylindrical hoppers had additional problems; but it would have nice to keep the original trucks and change out the high-rail wheelsets for prototypical scale wheelsets if one were not bothered by the excessive height of the bolsters. Those trucks are beautiful--but it costs $25 to replace the entire truck instead of salvaging the truck and changing just the wheels. (The subsequent auto-rack and reefer cars are too toy-like to appeal to prototypical modelers.) If Lionel ever decides to produce the once-promised mechanical reefers with the same level of detail as on the cylindrical hoppers--and correct height, they would be hit with both the prototypical and high-rail crowds if it were simple for prototypical modelers to purchase scale wheels and replace the included high-rail wheels and couplers.
There are also some S scale manufacturers who offer kits and some ready-to-run models that come with only prototypically scale trucks and wheels. If they also offered an option to supply high-rail wheels without fear of antagonizing their prototypical customers, they could reach some of the 85% + market share who appreciate the detail but who have already invested in high-rail switches and rail. S scale modelers, prototypical/high-rail/tin-plate, are too small a market to harbor the kind of animosity that sometimes resembles religious wars. If Lionel, for one, would continue to build-in the kind of consideration they showed in their SD70ACe models with easy-to-swap wheelsets, screws to fix pivoting pilots in place, and brackets for prototypical couplers, all camps would appreciate it. The reasonably priced Berkshires were an excellent move on their part. A Legacy version with the kind of detail found on the Y-3 and ability to easily add prototypical couplers would be a smart follow up. A second Legacy version with prototypical wheels would be too much to expect--but what a move that would be to make peace!
