I'm pretty sure the XP95 is the next, similar iteration of the GS95. I goofed around and tried the latter in some older irons about 5-6 years ago and was impressed. Easy to swing, felt almost like graphite, high flight and got great carry out of those irons without too much spin or the wind affecting them too much for a high launch shaft.
I play Nippon 1150s right now, a mid weight, mid launch shaft which I like and which fit me well. But later on down the line when age becomes more of a factor, I'll probably go with the XP95 or equivalent. I think you can probably hit almost any iron well with this shaft, even some modern blades. The forgiveness is in the shaft, and lightweight is the way to go for a lot of people.