I hover around 105-108. The best shaft I've ever played was a limited edition Accra Cs1...but I hit moon balls with it. everything else besides height was optimal (I was playing a 10.5 head at the time). Height of 140 on TM.
So any shafts I've tried after that, I've tried to find something as close in EI profile as possible (browsing the Accra s3 fitting software).
I tend to go with stiff flex, and tip it 1/2' to it plays about stiff and a half.
Currently paying a G410 LST (9º head, turned down to the Big minus...so actually playing loft is 7.5º) and the Ventus blue 6s, tipped 1/2".
I believe club loft plays way more of a factor in launch and height than does shaft. So I get the loft right and just "fine tune" with a shaft that fits my EI profile a la release pattern. Just my 2 cents!