My i7 2600 idles at 30°C idle. I am using the stock Intel fan. Lots of people on the forums are idling at the upper 30s or mid 40s regardless of brand CPU or fan...
You're good for sure, lot's of things can factor in, room temp, humidity, the mobo and how it sets voltages, thermal compound application, the case, airflow...I'd be perfectly happy with what you have