Stock 2g boost is 14 psi. No matter how many times I post this no one believes me. To bad the truth doesn't spread as fast as all the crankwalk myths do...
The stock 2g BOV wil start to leak well bfore 12 psi. More like 5. The question is at what point is the leak big enough to affect performance.
At 14 psi I doubt it is hurting you much. The factory didn't choose that BOV because they like to use shit parts that will hurt performance. Its an overboost protection as well. Same with the EVO BOV. The poewr gain poeple feel from upgradig the BOV is from the spike that an upgraded BOV no longer dampens. Spikes to ~17-19 psi are not uncommon on an upgraded BOV.