I won't ever go back to anything less than 110mm stem. Stability has been a huge confidence booster with a longer stem.
@
tetonrider it is interesting that you found a difference between the tarmac and venge descending/cornering. My future plan was always to drop a bike size and go with the venge over my current tarmac for several reasons. However, since adding length to my stem, I wonder if I had judged the tarmac too severely and perhaps will just drop a size for another tarmac.