Vietnamese restaurants can be found in most big cities (except Palm Springs, CA), so why the surprise in Vegas? And there are plenty of them. You have to count with both feet too if you really want to know.
To the point, it served just ordinary Pho. Maybe they are not really Vietnamese since they speak Cantonese.
We were the first customer at 10 AM on a Sat (Wendy's next door was my first choice but it opened at 11). I went straight to the Pho, item #1... the staple of Vietnamese dishes in USA. The broth was light and plain. It looked filtered, so was the flavor. It's a small bowl with pathetic amount of meats, not for the $7 in SoCal. Oop! I forgot. This was the touristy Vegas I'm talking about.
So diners, there are so many options, better options, out there. Do you really want to take a chance on Que Huong?