Hi all, Thinking of using one of these to run bass, keys, and guitar amp for busking. Says it can run up to 1500 w. I know that the draw from our instruments won't be more than 600 for bass, another 400 for guitar AND keys. None of that will be continuous. It's portable. It's powerful. It's rechargeable. Why isn't anybody talking about using these? I read something about you need a pure sine wave inverter, deep cycle batteries, blah blah. But this is all built into a cart with wheels already on it. Seems like a no-brainer. Noisy?