Stethoscopes

Which stethoscope is the best for nursing? I currently have a Littmann lightweight 2 and it is light but i can hear a lot of outer noises which is pretty distracting. I have tried the ADC double lumen style and they are nice but bulkier and heavier. I've heard that prestige is good, littmann classic, or littmann cardiology (kind of pricey though)? What do you use and prefer?