COD games 125fps or 144fps if you have a gsync 144hz gaming monitor ?

[thedoc46]

I've heard some conflicting information out there.

4690k, 16gb ram, GTX980 and XB270HU gsync monitor.

I like playing COD MW and BLOPS, BLOPS2

Should i set

/com_maxfps 125

or

/com_maxfps 144

Trying to understand why 125 would be better than 144 on the COD games. People say 125 for COD, but without explaining why.