I recently put together a set of TS3 irons with Nippon Modus 105 S shafts.  I LOVE the irons.  My two most common misses and thin and toe.  These irons have been great for those shots.  I know the thin shots benefit from the low COG of the irons but my solid shots are definitely high, bordering on too high.  All else being equal, how much of an impact would you expect the change to a DG 105 S300 shaft make in launch and peak height?  Like I said, I love the clubs, they feel great but I do feel as though I am losing out on some of my approach shots if I face any headwinds.