Golf WRX has explored this extensively. Have a read:www.golfwrx.com/.../

Small difference in weight between the two.

Hoganesque,

In answer to your Q - I've done both ie. soft-stepped the DG X100's and hard stepped the DG S400's in my MB's and AP2's.

I found in both sets that I tried it, the soft stepped X100's played (and felt) better in the 3-6 irons - mainly because the X100 is a lighter shaft than the S400.

However the 7-PW came out too low with the X100's soft stepped, and they felt very stiff with the hard stepped S400's in them, so I ended up going with standard S400 in the shorter irons both times.

However I've since found the new TT AMT shaft has almost eliminated the need for any shaft "stepping". The whole reason I tried 'soft steppping' and 'hard stepping' my shafts was for feel- not flex as there was virtually no noticeable performance (flight) difference between a hard stepped S400 and soft stepped X100. The AMT shaft has completely taken out the guesswork.

So If you are in between S400 and X100 in Dynamic Gold and you want a heavier club - go with the S400 Tour Issue AMT straight up and if you want it slightly lighter then go with the X100's in the Tour Issue AMT. No need to soft or hard step the AMT. You'll find the feel is great in the longer irons with the AMT and almost the same as before with Dynamic Gold in the shorter irons.

Hope that helps.

Cheers

Dave