M5 vs. SIM
To start I have to say I was basically committed to upgrading to the SIM this season seeing the positive buzz here and on the TXG vid. Hit them side by side on GC QUAD this weekend, actually have to say my M5 was surprisingly just as good and if not more stable and consistent. I do play my M5 weights in the most forgiving positions, which I feel makes it a better comp vs the weights being forward. What I saw was Same ballspeed and equally good spin stability on off-center strikes.
In the TXG comp, they never put the weights all the way back on the M5 which really in my opinion makes it more even with the SIM in terms of CG and MOI. The secret for M5 in my opinion is weight back, low loft to control spin. Set the M5 up like this go equal loft with the SIM and in my opinion there is just nothing there to go one way or another.
Bottom line, in this M5 weight-back configuration I see no significant upgrade.
Edit: to clarify, this is my setup. Loft is down at 7.75.
'16 M2HL 16.8 tour issued deep faced - Fujikura 8.3 TS
zU45 18 degree - S400
z745 4-PW - S400
SM6 50.08F - S400 Steel Gray
SM7 54.10S - S400 Raw
TM Hi-Toe 60.12ATV - S400 Black
TM Spider X - Navy