Tried for the first time today. I don't see what all the complaints are about, but maybe they had bad service or something a couple years back. The guy that served us today was quite nice, patient, and helpful. He even offered to let me try the serrano sauce without my asking him.
The wings were no bigger or smaller than any other wings I've ever had, the sauce was really good, and they were hot and fresh. I wasn't a fan of the fries. People have commented that they are soggy and coated with table sugar. I think them not being crispy is on purpose (you can select "crispy" on their web site), and I don't know that I tasted sugar on them. They seemed way, way salty to me.
While we were eating several other customers trickled in and I didn't see any of the people working there being rude to anyone.
Overall I thought the wings were good, the fries just aren't my speed (and I don't need the fries anyway), the store was clean, and the staff was friendly. I'll visit again.