Seriously? You say that my statement isn't true and you bring as an example the usb block erupters? ROI wise the worst miner in the history of bitcoin?
The only miner that noone ever made roi of?
I'm just telling you my experience. I have seen quite a few people say this crap for each device that is released, generally followed by, "you should just buy BTC instead" garbage. Your ability to ROI depends on your initial investment. Since mine was only $40 for 2.016GH/s, I didn't have far to go.