I visited this establishment today with "she who must be obeyed". The Portuguese have a saying "it doesn't smell good, it doesn't smell bad, it just doesn't smell". Sienna's fits into the latter category. It is difficult to criticise non existent service but when we were eventually served the waitress (I know, not PC) did arrive she was very pleasant. The food arrived in a reasonable amount of time and was OK.
So having joined the line of sheep to pay the bill at the register I left the restaurant wondering how to rate it. It was not worth more than three nor less than three so that is what rated it. I guess in Portuguese terms "it just does not smell".
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