What you will see is, during the day. Swim wear is prevelent. In the evening everyone will dress up. Men in slacks and a collared shirt. close toed shoes. Swim wear is frowned upon. It's the culture. People watch those going clubing you will see gowns and suits.
All of those are high end restaurants. Dress as you would back home.
Beachwear is out of character for all of those restaurants which are in an urban environment. Puerto Ricans dress up when they go out in the evenings.
I would never wear beachwear to those restaurants. I was more concern whether it is fine to wear polo short or dressing shirt with tie. I don't want to be over dress nor do I want to be under dress.
No tie is necessary. A nice shirt, slacks and dress shoes for the guy, nice dress slacks or dress and dress shoes for the girl.Edited: 8:41 pm, April 09, 2013
When we went to Marmalade, my husband wore khakis and a polo and I wore a skirt and blouse, not too fancy. Tons of people there were wearing shorts or jeans in the restaurant. He brought the long pants just for this restaurant and probably would just wear nice shorts and a polo next time to minimize packing. The chef was walking around and talking a lot in jeans too :)
For 1919 you should wear a suit for dinner. The restaurant is upscale & formal. You would not like to be underdressed. Not so for Marmalade, Casa de Espana or Pikayo.
Men in PR dress well and wear nice shoes to go out after dark. I found it impossible to wear a suit coat, but wore lightweight dark pants and a dress shirt and usually a tie to dinner and after. I didn't go to the clubs.Edited: 11:58 pm, April 09, 2013
I'd say for 1919 a nice long sleeve shirt and slacks, for the others a polo and slacks would be ok. No shorts please. Men in PR don't wear "nice shorts" to go out. Or sandals. I know that is acceptable summer attire in the US, but here you just look like a tourist. That said, my best friend from NYC always wears that when he visits, and I do take him around to nice restaurants :)