The cirumstances: it was late, and I was starving. When I'm at home, it's no problem to whip up something to eat or go to Zippy's at 1am. Not so easy when you're in Vegas and don't really know what's around.
I found out there was a Johnny Rockets in our hotel (Flamingo) and I actually saw an episode of "Undercover Boss" where the CEO of Johnny Rockets was on, so I decided I wanted to try here anyway.
Speed-wise, I feel like it could have been faster, but I'm kinda glad they don't mass produce everything and have it sitting like McD's. Prices are okay. I was VERY happy with their patty melt and fries. Nothing like a greasy cheesy burger-type sandwich in the middle of the night! Also got a milkshake the last night which was good.
All in all, super convenient and open at all hours. I liked the Flamingo and having Johnny Rockets right downstairs is a big plus!