I believe that legally, 2 piece bathing suits (belly exposing bikinis over tankinis, presumably) are prohibited in Sharjah. Public beaches in Sharjah are really not all that great, anyway, and Ajman is marginally better. I think is most hotel clubs, you'll be ok in a 2 piece bathing suit, but many will post rules stating that it's not allowed. Enforced at the hotels? I think this varies from one place to another. Enforced at the beach? I am told that in Sharjah it has been done. My own experience on the public beaches of Sharjah is that there seem to be lots more men there getting a good look...not the most comfortable of situations, but I urge you to check it out for yourselves.