Went Havana on a Friday night between 8-10pm for 2 people. Was pretty much 70-80% full downstairs with a couple of large groups. Firstly, the interior is beautifully decorated and lovely feel of sophistication. Wonderful food, not a very lareg choice on the menu, but didn't bother us as we both ordered the steaks. Not overly expensive for the quality of the food and the surroundings.
One thing, the bread they serve at your table before your meal was slightly tough for my liking. I like warm, fresh out the oven bread if they are offering. Personal preference. Also, when the restaurant did get slightly busy, I did notice the staff looked very busy catering to maybe too many tables per waiter(ess). This was not an issue for us but would have been nice for our plates to be taken quicker etc.
Would defiantly recommend this restaurant for couples and social groups, don't think this restaurant would be ideal with small children.