How did that turn out?
Judging by most of the internet retailers I checked, a Swift reefer is hard to find, but many others are on sale. Walthers page is strange, as it shows some as discontinued when sold out, and advanced reservations for others (but not any Swift schemes), as though there would be a second run.
Anyway, I would speculate that there is a market for more Swift cars, especially the red ones- just my two cents.
Hopefully, it worked well enough that Rapido is inspired to consider some other cars along the same line- which is to say, interesting cars that are a little off the beaten path (ie- NOT another version of something already produced by 3 other companies).