At the corner of Churchill and Gustavo Mejia Ricart, you cannot miss it, it's huge!
For the life of me I can't picture it, I guess we don't go by there much - and my in-laws live right off a corner of Churchill, but closer to the malecon. We usually just go to Plaza Lama - the traffic getting there is bad enough, guess we never fought our way much past 27 de Feb :squareeye
I like La Sirena in San Cristobal, do all our shopping for our house in Najayo Beach there, and never have trouble with the ATM outside it.