So what you're saying is that a product extant in the store doesn't do wha tyou want it to do, so you are making your own version that does, correct? That wouldn't be unfair, that would be simply competition. Unfair would be if you were to undermine the sales of the other set on it's own merits by, say, contacting renderosity and saying if they make it harder for him to sell than you you'll give them a bigger cut. That's business. It has a set of rules that are completely different from the other rules at play here: Artistry rules. What you are looking at is what I call artistic integrity in the marketplace. It's bad terminology on my part, but it basically means that folks in the marketplace have this habit of not doing what someone else has already done. A sign of a maturing market is the loss of that integrity. I say go for it. But it does tend to go against the grain of a lot of folks...

thou and I, my friend, can, in the most flunkey world, make, each of us, one non-flunkey, one hero, if we like: that will be two heroes to begin with. (Carlyle)