How does Genwa compare to Park's?
Very comparable...it's in my top 4. Parks is still my #1 (despite my last visit not being up to par). Genwa's meat quality is great, banchans are more about variety than anything but still generally great. If you haven't tried Genwa you should give it a shot. Perhaps try the new BH location as it takes reservations.
I work near Genwa and have gone countless of times... I think Parks is much better. Maybe I've missed something having only gone for lunch. But, I've gone so many times to Genwa that I've hit some off days, so maybe that's a reason why it's not one of my favorites.