both are working at the same pace.
VSC and NSC are both working at the same pace, VSC is one month a head, but anything can happen in future. Flip a coin and make a choice.
INS Nightmare,
If your head office is in VSC and you work in NSC region, you can start your GC at VSC and apply I-485 at NSC. I am in the same boat, but I applied at VSC.
good luck.