Based on physics and all that kind of stuff I'm not really a believer in shafts making a massive difference in spin.
However, I've recently been burning up some store credit by playing with various heads and shafts on a Foresight launch monitor.
Heads include Titleist 910, Epic, Epic SubZero, Cobra LTD, Callaway GBB and Callaway Fusion. Shafts include Rogue Silver, Rogue Black, Hzrdus Black, Hzrdus Yellow, Hzrdus T800, Matrix Xcon 6, Matrix Altus, Oban HB, Oban Purple, Oban Gold and others.
All of the head and shafts I've tested produce similar ball speed and launch angle.
Some of the heads produced higher spin (Epic and Titleist) than the others. The LTD was consistently lowest.
But to my annoyance certain shafts also produced notably lower spin than the others.
For me, the Hzrdus Black and Yellow spin around 700RPM less than the Rogues, for example. The Matrix Xcon is very close.
It could have been the swings on the day, but I got similar results over different sessions.
I should note that I have a strongly positive AOA and tend to be high launch and lowish spin in any case.
So the Hzrdus shafts with the LTD head produce the lowest spin for me.
Who knows what they might produce for someone else?