I wanted to try this on bass, but wasn't sure if I would like it as much as I thought, so I got this cheaper version of the popular E-Bow.
It does work quite well, though if you use it on bass like me, you may want to consider the following:
This product, just like the original E-Bow, is better suited for guitars. The grooves on the device are meant to fit around the 6 thin strings of a guitar and not so much on the 4 thick strings of a bass. It takes some extra practice to position the device correctly and actually get it to work, but that doesn't make this product bad, on the contrary.
My only complaint is that the magnetic field is not as strong as the E-Bow's, so the strings won't start vibrating as easily.
But for the price, it's a really good alternative. Though I will probably buy the original E-Bow in the future because of its better performance.
If you play guitar however, your strings are lighter and easier to vibrate, so you probably won't have this issue and this is even a better option for you.