Imitation is supposed to be the sincerest form of flattery. Although I doubt that's why Redman takes this route. If they aren't outright re-casts, and someone is simply reverse engineering them (in other words, producer plops a Rainman or Iminime down in front of sculptors and tailors and says : "Make ours look just like this one") then the producer (Redman) gets the best of both worlds. He has a ready made audience of people. Those who are/were impressed enough with the artists he is mimicking~~yet missed the boat due to expense or simply being late to the party. Whatever the case, Redman has found his niche. Some may say as a bottom feeder, others may argue as an affordable alternative.
I own a Rainman Psycho DX set. My wife sold her vacation days at work to buy it for me. A true sacrificing gesture, as she knows I love Psycho. I consider it one of the greatest horror vehicles ever made. If Redman reverse engineered this set to make it more affordable or accessible to those who missed it, it wouldn't bother me in the least. In point of fact, I may buy his set as well, especially if offered in color. Even if offered in Black and White, as the Rainman set was, I may get one. Because it would be cheap enough to re-paint the figures in color myself.
It's kind of like having an Amazing Spiderman #1, and getting upset because someone offers a reprint either in Marvel Tales, an Omnibus, a tpb, etc.
It's never going to affect the value of an original ASM#1. It also let's other folks be part of the party.
That aspect of all this I am totally ok with.
If the guy is just making molds of Rainman or Iminime's stuff (or Cult King or whomever), well then that's a whole different snuffiluffigus I guess.