As far as the topic of recasting models goes there are definitely three groups. Those who accept it, those who don't, and those who really don't care. If you read the first two articles on this then you have a good idea of what's going on. I guess that I will try to elaborate on this by applying my own experience and opinion.
First of all, I myself like to stay in the grey area. If someone is taking another's work and copying it purely to sell at lower prices and make a profit, then that isn't really acceptable to me. The model is readily available and being sold as it should be by the creator. It doesn't need to be duplicated by anyone else. However, I feel that certain circumstances may warrant the recasting of a model. My first instance of buying a recast involved the Godzilla vs. King Ghidorah kit. This is an amazing model that I knew I wanted no matter what. I was willing to pay any price, then I found out that it was a limited piece. This did depress me, as I knew it would raise the price. I was fifteen and only had what money I could get from mowing lawns, so I didn't have a good chance of buying an original. This is the case where I felt it was warranted to buy the recast. I got mine for half the price of what the original was selling for (which happened to be the total amount of money I took with me to the convention I bought it at). I seriously doubt that I would have that model if there were no recasts made of it. Some models, like the G vs. KG kit, are meant to be limited edition, but I think that in this hobby everyone should have a chance to proudly display any model on their shelves. Actually, I think it is a shame when people don't have the opportunity to work with models that are as beautifully done as this one was. So, I guess if a model just isn't available, either through production or original price, then a recast of it might be considered a credible service to those who weren't fortunate enough to get one.
Really, the decision to buy a recast is going to depend on your personal preference and the overall situation. My advice is to consider the credibility of the source and decide for yourself if the recast is reasonable.
One last thing, when considering whether or not to buy a recast, make sure you look it over! I have seen some of the most horrendous looking recasts, that frankly, wouldn't be worth the trouble. You never know what you could find.