For a 10% improvement I wouldn't pay more than $20-30 extra. That seems like a negligable improvement and I rather have the maker put in another half hour of craftmanship.
Personally I think steel material is way overrated. When was the last time a particular steel failed you? So long as the maker is using a steel with a good reputation I have no problem with it.
As collectors we have a mentality of collecting one knife of every steel type around. If new material didn't show up now and then, I suspect collector's interests would wane. We buy the "latest and greatest" largely because it is hyped up. If the consumer really knew it was a 10% improvement, I think he would be reluctant to buy it.
We collectors like makers who are open to new technologies. We rather have some guy that says "I tried the latest X steel and it's crap", than a guy that doesn't bother to experiment and is seen as out of the loop.
On the other hand the maker can "add value" to the steel. People buy Dozier's D2, Hartsfield's A2, Clark's L6 because we think they do an especially good job with them. None of these makers use the latest steels, but interests in them are just as strong.