I've eaten the noodle bowl with tuna. It was quite good. It comes served with sprouts and other veggies. I've also had the fresh spring rolls. They have many options to choose from.
I've also enjoyed the bubble teas. The Viet coffee, made with sweetened condensed milk, didn't suit me.
The Signature is a good neighborhood restaurant. It is a block from Seattle Center. The food is healthy but you don't feel like you're missing out on anything. I recommend it.