I live in South America , and it's always quite warm , always around 30c.
I have a Hyper 212+ with the stock fan in a Thermaltake Element T case, with 2 120mm front intakes of 70cfm each, a top 200mm 65cfm exhaust ( came with the case) and a 120mm 70cfm back exhaust. So the airflow is good. I achieved a nice cable management job in it too.
CPU is always at 3.6ghz, no cool n quiet, it idles at 40c and reaches 58-60c after 10 minutes of prime95, which does seem quite hot for the heatsink I have.
But then i see all those reviews are done with ambients of 20c or even less, and they get about the same if not more degrees -over ambient temp- than mine.
Looking at these results tells me that there are only a handful of coolers that would be better, and even then, they wouldn't be much better.
You might want to consider replacing the fan with one that pushes more air (the stock fan is rated for a max of ~77 CFM), such as these (note: pay attention to the DB, since that represents how loud this will be):