Well I decided to give GMB another go after my last attempt (they hadn't yet received their Banh Mi buns an hour after opening). I had to once again attempt to order a BBQ Beef Banh Mi.
After paying my $7.00+, I was a little shocked to see how little meat hit the grill. It sat over the hot flames for at least five minutes rendering it even smaller. I found it very odd that upon completion of the cooking of the beef, the "cook" quickly plated it and slid it through a window where the sandwich was "dressed" by someone else in the back kitchen. Odd because there was a full condiment bar right in front of me and I would have LOVED the ability to have request hot sauce and extra cilantro. What if I wanted no cilantro? What if...
When the guy came out of the back kitchen the sandwich was already wrapped and bagged so I decided not to complain about my inability to customize whatsoever.
As someone else suggested, it seems that you might have to keep on top of these guys when ordering a Banh Mi because it would seem that my bun was in the oven for the entire time that the beef cooked. It was completely devoid of any moisture and crackled in my mouth like a soda cracker. The flavours of the innards were good but this is a far cry from a good Banh Mi.
Good thing I know of two authentic Banh Mi joints not too far from this place.
I won't return.