This is my second pair of SB headsets, the first being the SB45 which I have used daily for over two years. The sound quality is fantastic, rich in tone and incredible clarity. The sound quality is on par with my old Sony MDRV6 (some of you will remember these were the top rated headphones back in the 90's) for about 1/3 the price without adjusting for inflation! The mic is top notch, big surprise for this price point, I sound as clear as my buddy using a $100 turtle beach kit. Some reviewers have complained that the mic doesn't flex and stay where you want it, but the mic doesn't have to be in your mouth, it picks up your voice with ease, even if it's a few inches from your lips . The isolation from the headphones is excellent, you are isolated from the outside world just by putting them on. They're also very comfortable, if a little big (but not overly heavy). More importantly, the flexibility of these headphones means they can be worn comfortably with just one ear closed (the ear cups pivot/fold for storage, the right cup can easily be flipped back to fit comfortably around your head), so you always have an ear free to listen to music. children when you need them. The microphone can be rotated up and out of the way when not needed. The cable is nice and long too, which is another great feature when you're away from your computer doing your own thing. The weak link in these headphones, as other reviews have pointed out, was the cable from my first set, which broke at the strain relief on the left ear cup. This was after two years of constant twitching, stumbling, and twitching from my toddlers, which I certainly consider abuse (on headphones, not kids =). They're not indestructible, but they're certainly durable, and after years of using the headset at least 4+ hours a day and testing literally dozens of different kits, I can wholeheartedly recommend it as the best mic and headset combo. Available up to $50. Whether you're listening to classical, country or rap, watching movies at high volume, leading a heist on 24 of your best friends or shouting at your wingman to clear your six, these headphones are a solid investment. (and with some preventative tape on the strain relief out of the box, it might be the last set you'll ever need.) The only difference between the SB49 and SB45 is the built-in volume control, they're otherwise identical. This headset confirms everything I've come to expect from Koss products: exceptional value for money, money left over to take my wife out to dinner to make up for all those hours on the computer.