I'm a little biased towards this location because 80% of my visits have been during late nights (when McDonalds after drinking didn't seem like an appetizing option) drawn mainly by their "adult milkshakes" and my experience then has been 2-3 stars but my breakfast trips here have definitely been at least 3 star experiences.
I must say that their location is amazing, so amazing in fact that sometimes the line up at night is annoyingly long, so if you're very hungry on a peak time, expect to wait longer or go somewhere else.
They have a full breakfast menu that will be sure to fill you up to the brim for a greasy start to your day (although you can change things around to eat healthier) and I must give it credit for totally giving off the diner vibe.
Staff experiences for me have been up and down, most of my night visits were impaired by below par service while during breakfast time it has on average been better.
For a breakfast place this is a good bet, and depending on what you want late at night they could fill that need too, don't expect very high quality or consistently great service.