I've thought about the Zia drive but they don't come up much. There's enough gain on the sex drive for me if I crank the drive. It sounds so good. But I like leaving it on all the time so much as my clean tone. It would be awesome to have another one for solos or just to stack with the one I already have. I'd have to try the Zia, see how it compares to the sex drive. I'm sure it's great if it's made by the same dude.