Any model that you measure closely, will mostly like have some inaccuracies. Some are due to compromises to allow it to run on our track which is 5 ft gauge and some due to wrong drawins sent or wrong interpretations. Remember the people that build these have never seen them and may have no idea what they are, they just work from whatever plans and drawings that are provided. And many of the importers are not modelers, simply businessmen, so they work with whatever is provided them by so-called "experts".
On the other hand, many issues in detail are often on the order of 3-6 scale inches, which is no big deal in my opinion.
As or electronics, most scale modelers in any scale have their preferences, so not being available in a brass steamer is also no big deal. Most of my HO buddies have favorite sound systems of various brands and rip out whatever comes in the loco and replace it with their favorites. I know a lot of BLI and Proto 2000 HO locos that have the electronics stripped out to put in "better" ones. So if you are going to install your own, why pay for whatever the importer puts in.
And the market does decide whether a model project will fly or not. Apparently at the price point Sunset wanted to meet, they could not get enough reservations for the SD40-2. Now in reality while the SD4-2 is considered modern by us old guys, it is an antique to the young guys and no longer seen on the big RRs as far as I know.
As for market, the Sunset GP7/9 announcement apparently went very well and that project is well on the way to production.
