Actually you can change the keys up so much you can do microtonal scales on it, but at the end of the day its a metallaphone so not likely to ever be the only piece of gear you'd want to use, you'd want to mix this with other gear to make a full sound.

“Essentially” in the sense you can’t really change the 8 frequencies you have to choose from quickly. Kinda impractical to do if you wanna play a set that spans different keys/tonalities.