I really like Smiths. The build quality and consistency from bass to bass is extraordinary with Smiths. I have a handful of basses from another high end boutique builder and every bass feels different when switching among 4, 5 or 6 strings. Each seems to have a different neck profile or thickness. With Smiths, every bass, whether it's a 4, 5 or 6, or a fretless, feels the same. Same neck profile, same thickness, same playability, same sound. Switching among them is effortless. I also like an extremely low action and I can get that easily with all of the Smiths. With other brands, the ultimate low action is hit or miss. My dealer once remarked that, for electric guitars, PRS was the only brand he felt comfortable drop shipping to customers because he knew the consistency was there and the customer would get a perfect guitar. Smith is that way for me.
And the sound, for me, is the ultimate in adaptable. It can be polite or reserved, or it can bark and bite if you dig into it. What comes out of the Smith is what my hands put into it because it is so playable. That's the key ingredient to a good sound.