From 1-4 it's a good feat.
But with step on the wind (disengage), open hand / shadow step / fist of the unbroken air, and stunning strike (can't use reaction), you have plenty of ways to avoid OA's at higher levels.
Maybe your DM will let you retrain.
The big difference is that all of these options cost ki, which is a limited resource, while Mobility is usable every round of every combat.