I am a closet DJ, and use Virtual DJ to create mixes for myself and friends. I was using a speaker set up without the sub, and always had issues determining the bass levels until after I was done and put the CD in my SUV. Wanted to buy something nice, but not needing to go all Bose, H&K, etc level. Just wanted to hear good sound. I researched a few places, and went to Best Buy to check out the demos. Let me tell you, I was happy with the demo, but when I brought it home, I was even happier. What a huge difference from what I had. The highs were sharper than some of the other ones priced from the $60-$80 range, and the mids came out strong. What impressed me the most was the bass. Being on my computer desk, I am able to really hear the different levels of bass. Obviously it will not compare to higher end uones (+$100), but for your money, it cannot be beat! So be realistic, you're not going to feel the bass hit you, but you will be able to hear the subtle levels of lows in a song.
The volume knob and headphone plug ins are nice features, but really, I was amazed at how much quality you get for around $55. If you want to improve your existing set up, hear some more detail in the music you are playing, and don't want to spend a whole lot, then I wholeheartedly recommend this product. I just did a 6 hour mix and was amazed at how nice it sounded while mixing.