I've used them and they are better than you would expect for $10 but that really isn't saying much.They can get you tracking for very little money but I'm sure that as soon as you can buy better you will.I had a bunch and I ended up giving them to the cheap F**ks that I jam with as they are better than the Radio Shack pieces of shit that these guys were using.
BTW,I played a benefit last weekend at a biker bar and the guy putting it on wanted to borrow some mics so we let him use the Starpowers and they didn't sound half bad.The thing is that they are so cheap that if they get dropped,broken or stolen they are so cheap it really ain't no big deal.