I had read about this place on HappyCow and was in town (June 2014), so I went in for a look. Here's my Saigon In and Out review.
The place is further up State Street going away from the ocean, a nice walk. It's a very large restaurant with deep interior and slightly dim lighting.
I asked about vegetarian choices, and the server gave me a separate vegetarian menu. On it were numerous choices, most items do contain some kind of mock meat. Not sure if the mock meats contain egg and whey, but I didn't bother to ask. I just wanted to eat Vietnamese veg food!
My family ordered a cold rice noodle dish that came with fried rolls and tofu. It didn't taste like as I had had at other Vietnamese restaurants. The tofu had a salty goey sauce which I didn't like.
We also tried one of the noodle soups, opted for mock chicken option. The soup had a good broth.
Then we shared an order of spring rolls (with tofu). That was okay.
Overall, I would say the vegetarian food is okay. I remember having better veggie/vegan versions at Loving Huts around the country. But, if you are craving vegetarian Asian/Vietnamese food, this is the only option here.