The name says it all. Come for the shakes and buns, but not for the burgers.
Holsteins is in the Cosmopolitan Casino on the 2nd floor shopping area. I was there a little after the lunch hour and had no problem getting a seat at the bar (I was flying solo until my peeps arrived in Vegas).
The service was decent and I quickly ordered the "Gold Standard" burger with dry aged sirloin, goat cheese, bacon, arugula and a wheat bun. Let's just say the burger was OK and the bun was the highlight.
Whatever taste of the sirloin was drowned out by the goat cheese. It was basically a goat cheese burger. The ingredients were fresh and the bun was the best hamburger bin I've ever had...but that isn't going to get it a 4-star rating.
The shoestring fries were cooked to perfection by extremely salty. Maybe it is to help you retain water in the desert climate. Or maybe the cook spent too much time on the Strip last night. Who knows?!
Bottom line. Holsteins was the typical flashy, overpriced midrange Vegas restaurant letdown. Good, but certainly not great...and not worth the price.