I have been to this location a couple times as well as the one in Markham and I really think that their quality is pretty consistent.
I love their food and, personally, I think their soup bases are less oily than other restaurants like Pho 88. I've tried their milkshakes here too and they are made well in my opinion. Service is really good and their waitresses are friendly and attentive. On my last visit, my mango milkshake was a bit sour so one of the girls named Hanna offerred to remake it. Regardless, the flavour was fresh so it was still good despite the sourness. You can actually TASTE the mango.
I usually get the House Special Pho because it has a variety of meats and its a good go-to. Most pho places really can't mess that up and if they do, then they have failed hard. Their sizes for bowls are reasonable and they give enough meat and bean sprouts. Not cheaping out on anything here which is great to know! I've also tried their Tom Yum soup options and their spicy beef stew noodles which are great too if you want some more flavour.
If there was a Lac Vien closer to where I live, I would make that my primary pho place. They have good variety and good quality plus pretty reasonable price. Sooooo what's not to like?