Folks, I was doing a clean up today and found an attenuator, it's the THD power Attenuator, 16 ohm Blue, still in its original box, never been opened, has a price tag on it of $329. I know nothing about attenuators. I bought it about 15 years ago when I had purchased one of my marshall Amps, the idea was I would use it in my bedroom. Never happened. Question is, is this a decent attenuator? Compared to all the other models I have been reading about here, where does this one stack up? Should I sell it, or use it? Thanks in advance for the advice.