The Flamingo has many highs and lows, and nothing in between. Super smokey casino that leaves your clothes reekin'? Check. Right in the center of the Strip for perfect access to anywhere? Check. A clientele that looks as though they enjoy the early bird specials? Check. A casino that has that old-Vegas touristy nostalgic feeling? Check and check.
Everyone should visit the Flamingo once. Even if it's just to stop in and make a lap before classin' it up at Bellagio or classin' it down at Bill's. I wouldn't recommend anyone spend most of their vacation there, however. It's crowded because it's in the middle of the Strip, but I get the feeling no one really wins while gambling here.
For a side note on the rooms.... my friend stayed in a "Go Room" this past week that I got to check out. It's large and has a mini-fridge for personal use. But it's got an odd design to it.... everything looks really plastic-y and there's opaque glass walls around the bathroom. And speaking of the bathroom, I hope you're comfortable with whomever you're shacking up with...you can hear everything that goes on in the bathroom and there are no locks on the door. The Flamingo is not a bad place to stay if you get a great deal, but I would consider elsewhere if the prices are comparable to other casinos.
In all, this a tourist casino. I can't imagine locals hanging out as regulars. Stop by to say you've seen it, and then move on to the next.