Just returned from our first holiday to Bulgaria, and we stayed in the Polyusi Apartments. We ate in the hotel's restaurants a few times and had excellent meals, highly recommend the Chinese. The meals at the hotel are a bit more expensive but it's handy. Hotel staff were very friendly and polite, and would do anything for you. The pool was very clean and they take away the sunbeds at 6pm and put them back out at 9am, so if you want a sunbed, be at the pool for 9am.
We drank at the Pool Bar and found that it can be more expensive than drinking in the bars just 10mins from the Hotel. Entertainment was poor, a woman and a keyboard everynight, after 1 week we could time when she would sing a certain song!! There is Bingo in the Cocktail Bar every night, with a Happy Hour from 7pm -8pm. I would highly recommend this hotel as the location is just a 10 minute walk from the main strip. Would definitely use this Hotel/Apartments again.
If using your ATM Card in Bulgaria, try and use the First Investment Bank, there are two branches on the main strip. We were getting a much higher exchange rate, anything from 2.45 to 2.51. Remember that your bank will probably charge you for a withdrawal, unless your with the Nationwide.