Within the past 4-5 months, my experiences at Pho So 1 have been bad but didn't want to rush to judgment until now.
I have tried Pho several times and other items that I normally ate at Pho So 1 and the food just weren't the same. I finally reached a conclusion: whoever managed the kitchen or whoever the main chef was, they must not be working there anymore.
First of all, the good old day Pho broth at PS1 wasn't great but at the same time it wasn't bad. Now, the broth tastes so bad, I don't come to PS1 for pho anymore. The broth tastes like somebody went to the Asian market and bought the dried pho flavor in a teabag pouch and dip that pouch into boiling water and served that to the customer. It was that bad.
Other food also did not taste the same. Beside Pho, PS1 was also known for their "Bo Nuong Vi", which basically allowed you to grill meet at the table. Their dipping sauce used to be soooooooooo good, but now it's smelly.
Another good indicator is the place is not crowded like before anymore. Too bad, because I used to like PS1. :-(